Pasteurella

Kansenshogaku Zasshi, 1991 Oct, 65(10), 1365 - 8
{A case of Pasteurella multocida subsp . multocida complicated with diabetes mellitus}; Yada T et al.; We report a case of sepsis who died caused by Pasteurella multocida subsp . multocide sepsis . A 68-year-old male was admitted to Azusawa Hospital because of disturbance of consciousness . He had been suffering from diabetes mellitus combined with gangrene, but received no treatment . The patient died 24 h after hospitalization, and Pasteurella multocida subsp . multocida was isolated from his blood . Laboratory tests showed that CRP; 5+ WBC; 15,400/microliters, TP; 5.2 g/dl . Although Pasteurella multicida subsp . multocida seemed to cause mild infection in healthy subjects, it can cause severe systemic illnesses such as sepsis and meningitis in compromised hosts . It should be considered that the contact with pets will increase the incidence of systemic severe infection with this agents.

Can J Vet Res, 1991 Oct, 55(4), 341 - 6
The microbial flora of the respiratory tract in feedlot calves: associations between nasopharyngeal and bronchoalveolar lavage cultures; Allen JW et al.; The upper and lower respiratory tracts of 59 feedlot calves with clinical signs of naturally occurring respiratory disease (cases) and 60 comparison (control) animals were cultured before treatment, using nasopharyngeal swabs (NPS) and bronchoalveolar lavage (BAL) . The most prevalent organisms were Pasteurella multocida and Mycoplasma bovis . Isolations of P . multocida from NPS and BAL fluid were found to be significantly associated with morbidity (p less than or equal to 0.05), but the frequency with which other organisms were isolated from the nasopharynx and lungs was similar in cases and controls . There was evidence of moderate agreement between NPS and BAL isolates at the individual calf level using the kappa statistic, (range of kappa values = 0.47-0.61) but the variability of the kappa statistics was large . Therefore, in an individual calf NPS cultures did not accurately predict BAL cultures . The NPS and BAL culture results were quite similar at the group level, however.

Zentralbl Veterinarmed B, 1991 Oct, 38(8), 599 - 609
Genomic distribution of a serotype 1-specific antigen-coding DNA fragment of Pasteurella haemolytica; Gonzalez C et al.; A genomic fragment of Pasteurella haemolytica biotype A coding for a serotype 1-specific agglutinating antigen was used as a probe in a series of hybridization experiments to determine distribution of the fragment in various P . haemolytica serotypes as well as other bacteria . Results showed presence of the fragment in seven out of the 12 serotypes tested, all of which belonged to biotype A . Two other serotypes belonging to biotype A, all three serotypes belonging to biotype T, two Pasteurella multocida isolates and Escherichia coli did not have the fragment in their genome . Thus the expression of the P . haemolytica biotype A serotype 1-specific agglutinating antigen (PHA1SAA) seems to be due to serotype-specific regulation of protein expression rather than to genetic deletion . Differences in methylation of the PHA1SAA-coding fragment was also noted in DpnI and Sau3AI genomic DNA digests from the various serotypes analyzed by Southern blot . However, no apparent correlation was observed between methylation and PHA1SAA expression . E . coli with a recombinant plasmid containing a homologous genomic fragment derived from P . haemolytica serotype 2 also expressed PHA1SAA.

Avian Dis, 1991 Oct-Dec, 35(4), 950 - 4
Genetic variation in resistance of turkeys to experimental challenge with Pasteurella multocida; Sacco RE et al.; Six hundred fifty-five male and female turkeys representing four genetic lines were challenged in 10 experiments over a 3-year period with a field isolate of Pasteurella multocida . Poults were challenged at 45 days of age with 1 ml of an inoculum containing 1.2 x 10(7) bacteria per ml . The lines of turkeys included two randombred control lines (RBC1 and RBC2), a subline (E) of RBC1 selected for increased egg production, and a subline (F) of RBC2 selected for increased 16-week body weight . The number of days from exposure to severe clinical signs or death for Line F (5.8 days) differed significantly from that of Line E (8.2 days), Line RBC1 (8.0 days), and Line RBC2 (8.2 days) . There were no significant differences due to sex of poult for number of days from exposure to severe clinical signs or death . Overall mortality observed was 51.2% . Mortality was highest for Line F (72.1%) and differed significantly from that of the other lines . Mortality among male poults did not differ significantly from mortality among female poults.

Avian Dis, 1991 Oct-Dec, 35(4), 761 - 6
Response of broiler chickens to fowl cholera vaccination at 1 to 6 weeks of age; Dick JW et al.; Broiler chickens, in groups of 10, received a single vaccination by the stick-wing route at 1, 2, 3, 4, 5, 6, or 11 weeks of age with live Clemson University strain of Pasteurella multocida . Twenty non-vaccinates kept in isolation served as controls . Cholera serum antibody titers in all chickens were determined by enzyme-linked immunosorbent assay at weekly intervals . Chickens vaccinated once at 1, 2, 3, 4, 5, and 6 weeks, respectively, attained 25.2%, 28.7%, 34.7%, 46.2%, 51.8%, and 64.6% of the titers of those vaccinated once at 11 weeks of age . Variation in antibody response was greatest in chickens vaccinated at 1 or 2 weeks of age . Additionally, chickens vaccinated at 1 or 2 weeks of age showed the longest response time (5 weeks) to reach maximum antibody titers after a single vaccination . When the original vaccinates were revaccinated at 11 weeks of age, all showed a secondary response equal to or greater than that seen in chickens vaccinated once at 11 weeks of age . Age of the chickens at the time of vaccination and antibody titer were positively correlated (r = 0.997) . Overall antibody responses to vaccination were higher and much more uniform as birds increased in age.

Am J Vet Res, 1991 Oct, 52(10), 1665 - 71
Pulmonary particle deposition and airway mucociliary clearance in cold-exposed calves; Diesel DA et al.; Effect of cold-induced changes in respiratory pattern on pulmonary particle deposition was investigated in 10 male Holstein calves between the ages of 1 and 3 months . Deposition of intranasally instilled fluorescence-enhanced Pasteurella haemolytica was significantly higher (P less than 0.05) for cold-exposed calves and appears to be caused by the cold-induced respiratory pattern change . Deposition was greater in apical and mediastinal lung lobes, but the reason for this preferential deposition is uncertain . Nasal mucus velocity was measured in 4 nonanesthetized calves at ambient temperature of 2 to 4 C and 16 to 18 C, using tantalum-paraffin oil droplets and serial radiography . Nasal mucus velocity was 24% lower during cold exposure . In addition, the effect of mucosal temperature on tracheal mucus velocity was determined in excised tracheas from 7 calves . A direct relationship existed between mucosal temperature and tracheal mucus velocity within the mucosal temperature range studied (35.0 to 39.5 C) . Tracheal air temperature measurements in calves at ambient temperatures of -10.4 C (n = 4) and 18.5 C (n = 5) indicated that conditioning of inspired air is not complete at the tracheal level during extreme cold exposure . Therefore, cold air may directly influence tracheal mucociliary clearance . It is speculated that cold exposure increases pulmonary deposition of pathogens, while simultaneously decreasing mucociliary clearance of the upper airways, thus predisposing cold-exposed calves to respiratory tract infection.

Am J Vet Res, 1991 Oct, 52(10), 1653 - 7
Resistance to antimicrobial agents and prevalence of R plasmids in Pasteurella multocida from swine; Cote S et al.; Twenty-nine field isolates of porcine Pasteurella multocida were characterized for their capsular and somatic types and were evaluated for their susceptibility to 10 antimicrobial agents . Plasmid DNA-screening experiments were conducted to determine whether a relationship existed between the presence of plasmids and antibiotic resistance . Field isolates of P multocida were susceptible to most of the antimicrobials tested, but all isolates were resistant to clindamycin . Eleven isolates of serogroup D were resistant to 1 or 2 antimicrobial agents . Resistance to sulfonamides and streptomycin was observed in 7 isolates . These isolates contained R plasmids conferring resistance to streptomycin and sulfonamides . The R plasmids belonged to 2 groups, one of 5.6 kilobase and the other of 5.9 kilobase . Restriction endonuclease mapping and DNA hybridization revealed that these R plasmids were related to RSF1010 from Salmonella panama, which also confers resistance to streptomycin and sulfonamides.

Am J Vet Res, 1991 Oct, 52(10), 1644 - 8
Electrophoretic profiles of Pasteurella multocida isolates from animals with hemorrhagic septicemia; Johnson RB et al.; We determined that the protein profiles of 14 isolates from animals with hemorrhagic septicemia were relatively homogeneous and could be placed in 2 distinct groups on the basis of their country of origin . Such differences correlated with the serotypic properties of the individual isolates; hemorrhagic septicemia isolates of Asian and North American origin (Carter B) had a major protein band with an apparent molecular mass of 32 kDa, whereas those of African origins (Carter E) had a major protein band with an apparent molecular mass of 37 kDa . The possession of a major 32-kDa protein band appeared to be unique to Carter B isolates, suggesting that electrophoresis may be a useful nonserologic technique for the identification of organisms of this serotype . Other major bands with apparent molecular masses of 27, 45, and 47 kDa were shared by all strains, regardless of their serotype . The lipopolysaccharides were of low molecular mass and relatively uniform from 1 isolate to the next.

J Vet Diagn Invest, 1991 Oct, 3(4), 324 - 7
Association of a Pasteurella haemolytica-like organism with enteritis in swine; McLaughlin BG et al.; A Pasteurella haemolytica-like organism was isolated from the intestines of 28 swine with clinical, gross, or microscopic evidence of enteritis . In 15 cases, other known enteric pathogens were also demonstrated, and in 13 cases, no other pathogens were detected . The mean age of affected animals was 44 days . Most of the animals had clinical evidence of diarrhea . Gross enteric lesions were present in 17 of 21 cases . Microscopic lesions were present in 24 of 26 cases . A diffuse or segmental moderate to severe necrotizing enteritis was the most common lesion in cases in which only the Pasteurella haemolytica-like organism was isolated . Biochemical tests gave results consistent with Pasteurella haemolytica, and 5 of 15 isolates met criteria for biotype A . Negative results were found with an indirect haemagglutination procedure for P . haemolytica.

J Vet Diagn Invest, 1991 Oct, 3(4), 319 - 23
Distribution of indole-producing urease-negative pasteurellas in animals; Biberstein EL et al.; Three hundred fifty-six animal isolates of indole-positive urease-negative cultures of Pasteurella, which would formerly have been classified as P . multocida, were examined with respect to their relationship to the recently described P . multocida subspecies (ssp.) multocida, septica, and gallicida and P . canis, P . stomatis/Taxon 16, and Pasteurella sp . B . Two hundred sixty-three (73.9%) of the cultures could be identified with one of these taxa, and 93 isolates (26.1%), representing 17 different biotypes, were unassignable . Pasteurella multocida ssp . multocida was the predominant taxon throughout and in most of the 25 animal species from which isolations were made . In dogs, P . canis was the most frequent . Different degrees of host predilection were observed also in P . multocida ssp . septica for cats, P . canis for sheep, and 2 of the unassignable biotypes for cattle and dogs, respectively . Overall, the respiratory tract was the most frequent source of isolates, but a propensity of P . multocida ssp . septica for localization in the central nervous system of cats was noted.

J Wildl Dis, 1991 Oct, 27(4), 685 - 7
Taxon 20 (Fam . Pasteurellaceae) infections in European brown hares (Lepus europaeus); Devriese LA et al.; Hemolytic bacteria, phenotypically related to organisms previously identified as Pasteurella haemolytica and tentatively named Taxon 20, were isolated from cases of purulent bronchopneumonia and from conjunctivitis in European brown hares (Lepus europaeus) . The bronchopneumonia, sometimes accompanied by lesions in other organs, occurred without other concomitant disease . The conjunctivitis was found mainly in animals suffering from the European brown hare syndrome.

J Wildl Dis, 1991 Oct, 27(4), 543 - 50
Correlations of daily activity with avian cholera mortality among wildfowl; Combs SM et al.; We tested the hypothesis that wildfowl activities can influence the risk of avian cholera (Pasteurella multocida infection) for susceptible birds at Centerville, Humboldt County, California (USA) . Avian cholera mortality characteristics from past epizootics were correlated with variations in flock size, habitat use and 11 feeding and nonfeeding behaviors among six empirically defined groups of wildfowl: American coots (Fulica americana), tundra swans (Cygnus columbianus), American wigeon (Anas americana), northern pintails (A . acuta), northern shovelers (A . clypeata)/mallards (A . platyrhynchos), and teal (A . discors, A . crecca, A . cyanoptera) . The position of these wildfowl groups in past mortality sequences was directly correlated with mean flock size, time spent on land, and time spent grazing on land or in shallow water . We propose that variations in bird density, habitat use and frequency of grazing may serve as predisposing factors to avian cholera among wildfowl.

Lab Anim, 1991 Oct, 25(4), 337 - 41
Pathogenicity of Pasteurella multocida A:3 in Flemish giant and New Zealand white rabbits; Dillehay DL et al.; Pasteurella multocida A:3 was isolated during an outbreak of pasteurellosis in Flemish Giant (FG) rabbits . Since New Zealand White (NZW) rabbits housed in the same room were not as severely affected as FG rabbits, experimental inoculation was undertaken to determine if FG rabbits were more susceptible than NZW rabbits to pasteurellosis induced by this isolate . Rabbits of each breed were inoculated with P . multocida A:3 and observed for 3 weeks . Four of 5 FG rabbits developed severe clinical disease on days 6, 9, 12 and 14 after inoculation; whereas, the one affected NZW rabbit became ill 14 days after inoculation . All rabbits with clinical disease developed fibrinosuppurative pleuritis, pyothorax and pneumonia which was more severe in FG than NZW rabbits . At necropsy, P . multocida A:3 was isolated from multiple sites of the diseased rabbits . No significant difference (P = 0.099) in the prevalence of lesions between the two breeds was found; however, the score of pneumonia and pleuritis was 3 times greater in FG rabbits than NZW rabbits.

Res Commun Chem Pathol Pharmacol, 1991 Oct, 74(1), 121 - 4
Exposure of sheep to Pasteurella haemolytica alters ex vivo pulmonary vascular smooth muscle alpha adrenergic responses: role of vascular endothelium; Weekley LB et al.; Sheep were exposed to a live- vaccine derived strain of Pasteurella haemolytica (10(5) colony forming units/sheep, i.m.) and euthanized 3 days later . Pulmonary artery and vein ex vivo responses to cumulative doses of methoxamine were determined . In some experiments endothelium was removed . In the pulmonary artery, removal of the endothelium significantly impairs the potency of methoxamine as a contractile agent in control sheep . Also, in sheep exposed to P . haemolytica removal of the endothelium ex vivo impairs the efficacy of methoxamine as a contractile agent . In the pulmonary vein, removal of the endothelium significantly increases the maximum contractile response obtained in control sheep . Conversly, in the pulmonary vein from P . haemolytica exposed sheep, removal of the endothelium reduces the efficacy of methoxamine . These experiments suggest that vaccination with live P . haemolytica impairs pulmonary vascular alpha adrenergic responses . Such impairments may contribute to development of pulmonary edema and congestion during stressful periods such as post-vaccination.

Lab Anim Sci, 1991 Oct, 41(5), 423 - 6
Partial characterization of plasmids from rabbit isolates of Pasteurella multocida; Gunther R et al.; Plasmids have not been reported for isolates of Pasteurella multocida from rabbits . We assayed 28 isolates of rabbit P . multocida for plasmids and sought to determine whether or not plasmid presence correlated with clinical or pathologic findings, serotype, toxin production, possession of pili, or biochemical characteristics . Fourteen isolates bore a single 1.6 Md (covalently closed circular form in 0.7% agarose gels) plasmid . An additional isolate had two plasmids which migrated as a closely-spaced doublet, centered around 1.6 Md . Eleven isolates appeared to have identical plasmids, according to Hae III and Hinf I digests . The apparent linear size of this common plasmid in 2% agarose gels was 2.1 Md, as calculated from the sums of the sizes of Hae III or Hinf I digestion fragments . Linearization of the common plasmid with Msp I produced an apparent size of 2.5 Md in 0.7% agarose gels . No correlations between presence of the common plasmid and somatic serotype, toxigenicity, presence of pili, antimicrobial resistance, selected biochemical characteristics, anatomic site from which the bacteria were cultured, or disease status of the host were found.

Lab Anim Sci, 1991 Oct, 41(5), 419 - 22
Screening rabbit colonies for antibodies to Pasteurella multocida by an ELISA; Zaoutis TE et al.; Rabbit serum samples from eleven different research facilities were evaluated for the presence of immunoglobulin G against Pasteurella multocida by using an enzyme-linked immunosorbent assay (ELISA) . Each facility which submitted serum samples also provided a brief history of each rabbit colony tested . Rabbits from colonies reported to have endemic P . multocida or of undetermined status had 83 (58.9%) of 141 rabbits that were positive . Colonies reported to be free from P . multocida had 110 (92.4%) of 119 rabbits that were negative by ELISA . The ELISA test described here showed a high degree of agreement (92-94%) with two other P . multocida ELISAs at different diagnostic facilities . This study confirms that an ELISA testing for serum antibodies against the P . multocida is a reliable diagnostic tool to screen colonies for P . multocida.

Exp Lung Res, 1991 Sep-Oct, 17(5), 939 - 57
Expression and kinetics of induced procoagulant activity in bovine pulmonary alveolar macrophages; Car BD et al.; Leukocytes, especially macrophages, are important cellular mediators of fibrin deposition and removal at tissue sites of inflammation . Pulmonary fibrin deposition is a prominent feature of bovine acute lung injury; therefore, we studied the resting and stimulated procoagulant responses of bovine pulmonary alveolar macrophages (PAM) and peripheral blood neutrophils (PMN) . Freshly isolated normal PAM and PMN expressed negligible procoagulant activity . PAM stimulated with endotoxin lipopolysaccharide (LPS), 4 beta-phorbol 12-myristate 13-acetate (PMA) and bovine recombinant interleukin-1 beta (rBIL-1 beta) exhibited protein synthesis- and dose-dependent enhancement of procoagulant activity in 8-h cultures . Bovine recombinant granulocyte macrophage-colony stimulating factor (rBGM-CSF) and recombinant human gamma-interferon (rHIFN-gamma) did not induce procoagulant activity . The kinetics of LPS- and PMA-enhanced PAM procoagulant activity differed: LPS-induced enhancement developed earlier and more rapidly than PMA-induced enhancement . Pasteurella haemolytica LPS was more potent than Escherichia coli LPS in enhancing PAM procoagulant activity, while dexamethasone decreased both baseline and LPS- or PMA-stimulated activity by approximately 50% . PAM procoagulant activity resulted from tissue factor expression . Bovine PMN produced negligible procoagulant activity when stimulated, and are thus unlikely to be major contributors to procoagulant activity in bovine lung . Activity inhibitory to bovine tissue factor was present in both calf and adult sera, and was partly dependent on the presence of factor X for activity . Rapid induction of bovine PAM procoagulant activity by inflammatory mediators, and subsequent resistance to degradation, may thus combine to promote an alveolar microenvironment permissive to fibrin deposition in bovine acute lung injury.

Br Vet J, 1991 Sep-Oct, 147(5), 437 - 43
Evaluation of combined Pasteurella vaccines in control of sheep pneumonia; Chandrasekaran S et al.; The effectiveness of an oil adjuvant vaccine (OAV) incorporating locally isolated strains of Pasteurella haemolytica type 7 and Pasteurella multocida types A and D was compared with that of Carovax (Wellcome Laboratories) in imported cross-bred lambs . The criterion of efficacy was the ability of the vaccines to reduce the extent of pneumonic lesions in vaccinated as against unvaccinated control lambs . The OAV produced at this Institute significantly reduced the lung lesions at P less than 0.05 level compared with its control group when challenged with P . haemolytica alone . However, the vaccine was unsatisfactory against P . multocida or combined P . multocida P . haemolytica challenge . Carovax did not produce any significant reduction in the lung lesions caused by P . haemolytica and/or P . multocida.

Br Vet J, 1991 Sep-Oct, 147(5), 413 - 20
A field investigation of subclinical mastitis in sheep in southern England; Watkins GH et al.; The prevalence, aetiology and epidemiological features of subclinical mastitis were investigated in 358 lowland ewes in seven flocks in southern England . Milk samples (2092) were collected at 3-weekly intervals; those which were both bacteriologically and Whiteside test positive were deemed to have originated from glands with subclinical mastitis . The period prevalence of subclinical mastitis was 11.7% and the prevalence remained relatively constant over the course of lactation (5.5-7.0%) . The predominant bacterial isolates from 48 glands with subclinical mastitis were streptococci (42%), coagulase-negative staphylococci (33%), Pasteurella haemolytica (17%) and Staphylococcus aureus (8%) . Coagulase-negative staphylococci were the predominant isolates (53%) from samples which did not show a positive Whiteside test result . The prevalence of subclinical mastitis increased with age of ewe but was not influenced by the presence of teat lesions . There was a significant association between the development of clinical mastitis (26 glands) and antecedent subclinical mastitis caused by the same organism (10 glands).

Infect Dis Clin North Am, 1991 Sep, 5(3), 663 - 80
Infections resulting from animal bites; Weber DJ et al.; Animal bites are a major public health problem . This article reviews the epidemiology and treatment of animal bites . The epidemiology, clinical presentation, and treatment of infections caused by Pasteurella multocida and Capnocytophaga canimorsus (DF-2) are reviewed in detail.

Berl Munch Tierarztl Wochenschr, 1991 Sep 1, 104(9), 298 - 303
{Pasteurella multocida as the cause of disease outbreaks in commercial poultry flocks}; Hinz KH et al.; Six cases of fowl cholera in growing turkeys and 3 in adult breeder chickens of the broiler type as well as one case each of a Pasteurella (P.) multocida-associated disease in ducklings and goslings were described in consideration of own laboratory findings and available informations of the case history . Furthermore a report is given on a treatment strategy successfully used in turkeys with highly acute fowl cholera . All the P . multocida strains isolated culturally could be assigned to the subspecies multocida . In one case Bordetella avium, Salmonella (S.) arizonae and S . hadar were additionally cultured form part of turkeys submitted . P . multocida and Moraxella (Pasteurella) anatipestifer could be determined as the causative agents of the disease of ducklings and goslings . P . multocida strains from turkeys were identified serologically as serovars A:3.4 (3x), F:3.4 (2x) and A:3 (1x); those from the breeder chickens as A:3 (3x); and one each from ducklings and goslings as F:3.4 and -:3 . (uncapsulated) . No death occurred in turkeys with clinical signs of a highly acute fowl cholera if the treatment of the affected birds was started with an intravenous injection of sulfadimethoxine and continued with a combination of sulfachlorpyridazine (SCP) and trimethoprim (TMP) given in the drinking water for 5 days . However relapse occurred 2-3 days after withdrawal of the drug, although the therapy was clinically highly effective . The recurrence of the disease could be prevented reliably if the turkeys were vaccinated with an effective oil-based bacterin and subsequently treated with the SCP-TMP combination given in drinking water over a 12 day period.

Am J Vet Res, 1991 Sep, 52(9), 1507 - 11
Resistance of Pasteurella multocida A:3,4 to phagocytosis by turkey macrophages and heterophils; Harmon BG et al.; A virulent field isolate and 2 vaccine strains of Pasteurella multocida A:3,4 were compared for resistance to phagocytosis by turkey macrophages and heterophils, using in vitro assays . The least virulent vaccine strain (M-9) was phagocytosed to a greater degree than was the field isolate or the other vaccine strain (Clemson University) . All 3 bacteria differed significantly from each other in the amount of capsular material present as measured by polycationic ferritin labeling and electron microscopy . Removal of the capsule with hyaluronidase resulted in a significant increase in phagocytosis of the field isolate.

J Bacteriol, 1991 Sep, 173(18), 5597 - 603
Cloning, nucleotide sequence, and expression of the Pasteurella haemolytica A1 glycoprotease gene; Abdullah KM et al.; Pasteurella haemolytica serotype A1 secretes a glycoprotease which is specific for O-sialoglycoproteins such as glycophorin A . The gene encoding the glycoprotease enzyme has been cloned in the recombinant plasmid pH1, and its nucleotide sequence has been determined . The gene (designated gcp) codes for a protein of 35.2 kDa, and an active enzyme protein of this molecular mass can be observed in Escherichia coli clones carrying pPH1 . In vivo labeling of plasmid-encoded proteins in E . coli maxicells demonstrated the expression of a 35-kDa protein from pPH1 . The amino-terminal sequence of the heterologously expressed protein corresponds to that predicted from the nucleotide sequence . The glycoprotease is a neutral metalloprotease, and the predicted amino acid sequence of the glycoprotease contains a putative zinc-binding site . The gene shows no significant homology with the genes for other proteases of procaryotic or eucaryotic origin . However, there is substantial homology between gcp and an E . coli gene, orfX, whose product is believed to function in the regulation of macromolecule biosynthesis.

Infect Immun, 1991 Sep, 59(9), 3126 - 33
Activation of bovine neutrophils by partially purified Pasteurella haemolytica leukotoxin; Czuprynski CJ et al.; In this study we developed a new method for the partial purification of Pasteurella haemolytica leukotoxin by size-exclusion high-performance liquid chromatography . The partially purified leukotoxin had a molecular weight of 104,000, as estimated by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and reacted on an immunoblot with an antileukotoxin monoclonal antibody . As expected, high concentrations of the leukotoxin were inhibitory or lethal to bovine neutrophils . Incubation of bovine neutrophils with diluted leukotoxin, however, resulted in significant neutrophil activation that was comparable in magnitude to that obtained with standard activating agents such as opsonized zymosan or zymosan-activated serum . Dilute leukotoxin (1:128 to 1:8,192 dilutions) stimulated an oxidative burst (luminol-dependent chemiluminescence) by bovine neutrophils that was comparable in magnitude to that obtained with opsonized zymosan . Preincubation with leukotoxin did not significantly prime the neutrophils for an enhanced oxidative burst when they were then exposed to opsonized zymosan as a second stimulus . Dilute leukotoxin (1:100 to 1:1,000 dilutions) also stimulated cytoskeletal alterations in bovine neutrophils, as measured by a significant shape change response . Preferential release of secondary granule constituents (lactoferrin) occurred when neutrophils were incubated with 1:100 to 1:500 dilutions of leukotoxin . Significant release of primary granules, as measured by beta-glucosaminidase activity, was not observed except at low dilutions (1:20) of leukotoxin that resulted in significant release of cytosolic constituents (i.e., lactate dehydrogenase activity) . The neutrophil-activating activity of the leukotoxin was heat labile, unaffected by polymyxin B, and abrogated by a leukotoxin-neutralizing monoclonal antibody . These data indicate that P . haemolytica leukotoxin, like the closely related Escherichia coli hemolysin, is a potent neutrophil-activating agent . Leukotoxin-stimulated release of neutrophil oxygen intermediates and granule constituents may contribute to the intense inflammation that characterizes bovine pulmonary pasteurellosis.

Infect Immun, 1991 Sep, 59(9), 3026 - 32
Nucleotide sequence of the hemolysin I gene from Actinobacillus pleuropneumoniae; Frey J et al.; The DNA sequence of the gene encoding the structural protein of hemolysin I (HlyI) of Actinobacillus pleuropneumoniae serotype 1 strain 4074 was analyzed . The nucleotide sequence shows a 3,072-bp reading frame encoding a protein of 1,023 amino acids with a calculated molecular size of 110.1 kDa . This corresponds to the HlyI protein, which has an apparent molecular size on sodium dodecyl sulfate gels of 105 kDa . The structure of the protein derived from the DNA sequence shows three hydrophobic regions in the N-terminal part of the protein, 13 glycine-rich domains in the second half of the protein, and a hydrophilic C-terminal area, all of which are typical of the cytotoxins of the RTX (repeats in the structural toxin) toxin family . The derived amino acid sequence of HlyI shows 42% homology with the hemolysin of A . pleuropneumoniae serotype 5, 41% homology with the leukotoxin of Pasteurella haemolytica, and 56% homology with the Escherichia coli alpha-hemolysin . The 13 glycine-rich repeats and three hydrophobic areas of the HlyI sequence show more similarity to the E . coli alpha-hemolysin than to either the A . pleuropneumoniae serotype 5 hemolysin or the leukotoxin (while the last two are more similar to each other) . Two types of RTX hemolysins therefore seem to be present in A . pleuropneumoniae, one (HlyI) resembling the alpha-hemolysin and a second more closely related to the leukotoxin . Ca(2+)-binding experiments using HlyI and recombinant A . pleuropneumoniae prohemolysin (HlyIA) that was produced in E . coli shows that HlyI binds 45Ca2+, probably because of the 13 glycine-rich repeated domains . Activation of the prohemolysin is not required for Ca2+ binding.

Agents Actions, 1991 Sep, 34(1-2), 197 - 9
An in vitro model system to evaluate pulmonary macrophage, endothelial cell, and neutrophil interactions; Sharma SD et al.; Pasteurella haemolytica, the cause of fibrinous pleuropneumonia in cattle, produces extensive microvascular endothelial cell (EC) damage . We have developed an in vitro model system to study the inflammatory process of this disease involving the interaction of pulmonary alveolar macrophages (AM), neutrophils (PMN), and EC . Bovine EC are grown to confluency in 24 well tissue culture plates . To mimic the vascular component, 10(6) PMN are later added to the EC monolayers . Bovine AM are plated onto millicell inserts and placed into the wells containing EC and PMN . The millicell insert serves as a semi-permeable barrier between AM and EC, allowing the exchange of only diffusible material . Preliminary work demonstrates that P . haemolytica stimulated AM resulted in EC damage presumably due to both soluble lipopolysaccharide and AM secreted products.

Res Vet Sci, 1991 Sep, 51(2), 203 - 8
Occurrence and diversity of plasmids in ovine isolates of Pasteurella haemolytica; Wood AR et al.; 160 ovine isolates of Pasteurella haemolytica, representing each of the 16 serotypes and also untypable strains, were examined for plasmid content . Plasmid DNA was identified in, and prepared from, strains of serotypes A2, T3, A14 and A16 and also from an untypable strain . The relationship between the plasmids present in the different strains was examined both by restriction fragment profile analysis and by DNA/DNA hybridisation . Both methods gave broadly similar results and showed that each serotype tended to contain either a single plasmid species, or a limited range of species, and that structural similarities could traverse serotype boundaries . None of the plasmid-bearing strains showed any significant level of resistance to a range of antibiotics.

Res Vet Sci, 1991 Sep, 51(2), 209 - 14
Protective effect of inactivated bovine herpesvirus-1 in calves experimentally infected with bovine herpesvirus-1 and Pasteurella haemolytica; Jericho KW et al.; The protective effect of an inactivated whole-virion bovine herpesvirus-1 (BHV-1) immunising inoculum, without adjuvant, against viral-bacterial respiratory disease was studied in three experimental treatment groups of five calves each . One group was boosted 14 days after the first vaccination and at this time the second group received their initial inoculation . Seven days later, calves were challenged with BHV-1 in aerosol and four days after this challenge all calves were exposed to Pasteurella haemolytica A1 in aerosol . Among the three groups, differences in rectal temperature responses four days after viral challenge (P less than 0.01) did not relate to protection . However the main response variable, viral-bacterial pneumonia, was reduced in boosted calves (P less than 0.05).

Vet Immunol Immunopathol, 1991 Aug, 29(1-2), 57 - 68
Preliminary investigation of the mechanism of inhibition of bovine lymphocyte proliferation by Pasteurella haemolytica A1 leukotoxin; Majury AL et al.; Pasteurella haemolytica A1 leukotoxic culture supernate has been shown to inhibit bovine lymphocyte blastogenesis induced by concanavalin A (Con A), pokeweed mitogen (PWM) and purified protein derivative (PPD) . The various mechanisms by which this inhibition could be overcome were investigated in an effort to determine at which stage of cell activation the leukotoxin exerted its inhibitory effect . For both Con A and PWM stimulated cultures, the addition of partially purified bovine interleukin 1 reduced the leukotoxin-induced inhibition . Recombinant interleukin 2 had a similar effect . Addition of the glycolipid, monosialoganglioside was also able partially to overcome the inhibition.

Vet Immunol Immunopathol, 1991 Aug, 29(1-2), 41 - 56
The effect of Pasteurella haemolytica A1 leukotoxic culture supernate on the in vitro proliferative response of bovine lymphocytes; Majury AL et al.; The effect of sublethal concentrations of the Pasteurella haemolytica leukotoxic culture supernate on bovine lymphocyte blastogenesis was investigated . Blastogenesis in cultures stimulated with either concanavalin A (Con A) or pokeweed mitogen (PWM) was inhibited in the presence of the supernate, as was the response to purified protein derivative in lymphocytes from BCG-vaccinated cattle . Partially purified leukotoxin had a similar effect . Pre-incubation of the leukotoxic supernate with a polyclonal rabbit antiserum raised to the immunogenic molecule of recombinant leukotoxin (r LktA) abrogated this effect, implicating leukotoxin as the factor responsible for the inhibition . B cell enriched cultures tended to be more sensitive to leukotoxic effects than did T cell enriched cultures . Although only ruminant cells are susceptible to the lethal effects of P . haemolytica leukotoxin, the toxin did inhibit both Con A- and PWM-induced proliferation of human and dog lymphocytes . As well, at high leukotoxin doses, Con A-stimulated pig lymphocyte proliferation was reduced . Rabbit lymphocytes were not affected by leukotoxin in either Con A- or PWM-stimulated cultures.

Dtsch Tierarztl Wochenschr, 1991 Aug, 98(8), 310 - 2
{Detection of neutralizing antibodies against Pasteurella multocida toxin in swine with atrophic rhinitis}; Bechmann G et al.; Blood sera of 1171 pigs, not vaccinated against PAR, were tested for antibodies against P . multocida toxin in a neutralization test with EBL cell cultures . 277 sera were from 18 herds with clinical PAR; 104 of them (37.5%) had neutralizing antibody titres from 1:2 to 1:1024 . No antitoxin was detected in the sera of 866 pigs in 25 PAR nonsuspicious herds . In one nonsuspicious herd, however, 11 of 28 sera were neutralizing in the 1:2 or 1:4 dilution . 30 sows had been vaccinated with inactivated toxigenic P . multocida and/or with the P . multocida toxoid . 21 of these sows had neutralizing sera with titres between 1:8 and 1:4096 . The neutralization test presented can be applied for herd diagnosis of PAR and for demonstration of vaccination effects.

Am J Vet Res, 1991 Aug, 52(8), 1245 - 51
Actinobacillus suis-like organisms and evidence of hemolytic strains of Actinobacillus lignieresii in horses; Samitz EM et al.; Thirty-seven local isolates of Actinobacillus suis-like organisms from diseased and clinically normal horses and 1 llama were compared with reference strains of A suis, A lignieresii, A equuli, A capsulatus, A hominis, A (Pasteurella) ureae, and equine A suis-like organisms (ASLO) previously described in literature . Comparison was by cultural characteristics, carbohydrate fermentation, enzyme profiles, and whole-cell protein polyacrylamide gel electrophoresis . Carbohydrate fermentation, determined by API-CH gallery, divided 36 equine ASLO isolates into 6 API-CH biotypes . The llama isolate was an additional distinct biotype . The biochemical comparisons between A suis and ASLO did not reveal remarkable and consistent differences . Enzyme analysis revealed 5 API-ZYM biotypes, one of which included the same strains as one of the API-CH biotypes and consisted in both instances of 4 esculin-negative ASLO cultures and the reference strain of A lignieresii . We conclude that the 4 strains were hemolytic variants of A lignieresii . Protein electrophoresis disclosed 15 banding patterns, 10 of which represented equine ASLO strains . The reference strains of A suis shared the pattern predominant among equine ASLO . Four of the remaining reference strains of Actinobacillus species each had a unique profile, whereas the type strain of A capsulatus and the llama isolate had similar profiles . The groupings of cultures resulting from the different testing methods had little relation to each other and to the anatomic source of the strains except the strains comprising API-CH biotype II, which originated in the equine respiratory tract, and the A lignieressi cluster.

Am J Vet Res, 1991 Aug, 52(8), 1214 - 20
Comparison of four immune variables and pulmonary lesions of goats with intrapulmonary exposure and subsequent intrathoracic challenge exposure with Pasteurella haemolytica; Purdy CW et al.; A comparison of immune variables following lung sensitization with live Pasteurella haemolytica serotype 1 (Ph1)-impregnated agar beads was done in 2 separate trials . The Ph1 immune variables studied were blood bactericidal activity, serum bacteriolysis, total classical complement, and indirect hemagglutination antibody . Each trial had 16 male weanling goats: 6 controls and 10 principals . In trial 1, each goat was surgically catheterized through the trachea, then the material was deposited in a bronchus . The controls received only agar beads and the principals received agar beads impregnated with live Ph1 . These goats were studied for 32 days, euthanatized, and necropsied . In trial 2, the controls were each transthoracically injected with agar beads into the left lung and the principals were similarly injected with agar beads impregnated with live Ph1 . These goats were studied for 35 days, then challenge exposed transthoracically by injection of Ph1 in saline solution (1.2 x 10(7) CFU/ml) into the right lung . Four days later, they were euthanatized and necropsied . The volume of lung consolidated tissue was an excellent measure of Ph1 immunity . Principal goats generated solid protective immunity to subsequent challenge exposure because minimal or no lung consolidation was observed, whereas large volumes of lung consolidation were seen in the controls . The principal goats in trial 1 gave a weak serum indirect hemagglutination Ph1 antibody response, which was attributed to the bronchial method of depositing the Ph1 . The corresponding response of the control group remained negative . The Ph1 agar beads (1 x 10(6) CFU in 0.5 ml) protected the bacteria from immediate phagocytosis and lysis as indicated by the induced pneumonic deaths of 2 principals 5 days later.(ABSTRACT TRUNCATED AT 250 WORDS)

Poult Sci, 1991 Aug, 70(8), 1704 - 8
A retrospective analysis on the epizootiological aspects of outbreaks of Pasteurella anatipestifer infection in turkeys in Minnesota; Charles SD et al.; The possible risk factors associated with outbreaks of Pasteurella anatipestifer infection in turkeys were analyzed to study the epizootiology of the disease . The data for the study was obtained from flocks affected and unaffected with Pasteurella infection . The results of the analysis suggested that overcrowding, preexisting viral infections, increased activity of wild birds on the farm, and shorter down time were possible factors that initiate the occurrence of the disease in turkey flocks . The statistical models used in the analysis predicted correctly 80% of the unaffected flocks (8 out of 10 flocks), and 95% of the affected flocks (13 out of 14 flocks) . The overall correct prediction was 88% (21 out of 24 flocks) . Fish meal and meat and bone meal, which are integral components of turkey feed, were analyzed for the possible presence of P . anatipestifer . Its presence in a sample of fish meal was demonstrated.

J Bacteriol, 1991 Aug, 173(16), 5151 - 8
The Actinobacillus pleuropneumoniae hemolysin determinant: unlinked appCA and appBD loci flanked by pseudogenes; Chang YF et al.; The appBD genes encoding the secretion functions for the 110-kDa RTX hemolysin of Actinobacillus pleuropneumoniae have been cloned and sequenced . Unlike analogous genes from other RTX determinants, the appBD genes do not lie immediately downstream from the hemolysin structural gene, appA . Although isolated from a diverse group of gram-negative organisms, the appBD genes and the characterized RTX BD genes from other organisms all exhibit a high degree of homology at both the DNA and predicted amino acid sequence levels . Analysis of the DNA sequences 3' to appA and 5' to appB suggests that these regions harbor remnant RTX B and A pseudogenes, respectively . Although the appA gene is most similar to the lktA gene from Pasteurella haemolytica (Y . F . Chang, R . Young, and D . K . Struck, DNA 8:635-647, 1989), the RTX A pseudogene upstream from appB most closely resembles the hlyB gene from Escherichia coli, suggesting that the appCA and appBD operons were derived from different ancestral RTX determinants.

Mol Gen Mikrobiol Virusol, 1991 Aug, (8), 29 - 32
{Isolation and certain properties of the dermonecrotic toxin from Pasteurella multocida}; Kalmykova LI et al.; The procedure for isolation and purification of Pasteurella multocida serovariant D toxin has been described . It includes the three steps of protein precipitation from cultural filtrates by 70% ammonium sulfate, chromatography of the concentrated material on Ultragel AcA44 gel-filtration on Sephracryl S-200 . The proposed technique permits one the 155-fold purification of the preparation with 32.6% yield estimated by biological activity . The obtained purified preparation is homogeneous in polyacrylamide gel electrophoresis . The immunological methods also confirm the homogeneity of the preparation . The minimal dermonecrotic dose for guinea pigs of the purified 120 kDa toxin is 78 ng and LD50 for mice is 280 ng . Pasteurella multocida toxin is found to be a thermolabile protein sensitive to trypsin, glutaraldehyde and formaldehyde treatments.

J Comp Pathol, 1991 Aug, 105(2), 157 - 66
Immune responses of lambs experimentally infected with bovine respiratory syncytial virus and Pasteurella haemolytica; Sharma R et al.; The immune responses of lambs experimentally infected with bovine respiratory syncytial virus (RSV) and Pasteurella haemolytica were compared with lambs infected with bovine RSV or Pasteurella haemolytica alone . Superinfection with P . haemolytica aggravated the reduction in the number of CD5+, CD4+ and LCA p220+ (B) lymphocytes caused by bovine RSV, but it had no effect on the neutralizing antibodies against P . haemolytica cytotoxin . Serum samples obtained from lambs experimentally infected with bovine RSV and P . haemolytica had significantly lower amounts of neutralizing antibodies to bovine RSV than those obtained from lambs infected with bovine RSV alone.

Am J Vet Res, 1991 Aug, 52(8), 1345 - 9
Molecular epidemiology of Pasteurella multocida in turkeys; Carpenter TE et al.; Pasteurella multocida isolated from turkeys during an outbreak of fowl cholera was characterized by serotype and heterogeneity of genes encoding rRNA (ribotype) to investigate the epidemiology of the organism . Isolates were collected between October 1985 and July 1986 . The M9 or Clemson University fowl cholera vaccine-like strain was detected in 17% of the flocks with fowl cholera . One particular strain, isolated only from breeder flocks, was recovered from 7 of the 10 breeder flocks examined in this study . Intracompany transmission appeared to be common, implying a failure in biosecurity . Circumstantial evidence indicated that in the field; the incubation period of P multocida in a turkey flock may be between 2 to 7 weeks . Wildlife did not appear to be an important reservoir of P multocida for turkeys during this study period . Ribotyping results tended to discount several of the possible interflock transmissions, as suggested by examination of serotyping results alone; however, serotyping in combination with ribotyping proved helpful in understanding the epidemiology of P multocida in turkeys.

J Comp Pathol, 1991 Aug, 105(2), 203 - 11
Clinical chemical constituents in relation to liver amyloidosis in serum-producing horses; Abdelkader SV et al.; Serum activities of gamma-glutamyl transferase (GGT), alkaline phosphatase (AP), aspartate aminotransferase (AST), and concentrations of total bilirubin and total bile acids were screened during a 5 year period in 27 horses used for production of hyperimmune serum . The horses investigated were regularly immunized with live cultures of the endotoxin-releasing bacteria Escherichia coli or Pasteurella multocida, the individual animals having undergone such treatment for periods varying from 2 weeks to 10 years . In a majority of the horses, GGT-activity had increased within 6 to 7 years of first having undergone immunization . Constantly high values seemed to co-incide with the presence of advanced liver amyloidosis, as demonstrated by histopathological examination after slaughter . The AP activity was also increased but only moderately compared with GGT . Individual values more than 10-fold greater than the upper reference limit were recorded for GGT, while the highest AP values were less than double the upper reference limit . Activity of AST and bilirubin concentrations remained unaffected, whereas the concentration of total bile acids rose after 6 to 7 years of immunization compared to the baseline value . It is concluded that the determination of serum activities of GGT may serve as a practical routine test for the evaluation of liver amyloidosis status in serum horses.

Mutat Res, 1991 Jul, 263(3), 159 - 63
Pasteurella haemolytica is highly sensitive to ultraviolet irradiation; Lo RY et al.; The response of Pasteurella haemolytica to ultraviolet irradiation was determined . The results for survival show that P . haemolytica is very sensitive to UV-irradiation . This UV-sensitivity is similar to E . coli strains defective in UV repair mechanism(s) . Analysis of the distribution of TCA insoluble versus TCA soluble {3H}thymine dimers in UV-irradiated DNA of P . haemolytica during a 2-h post-irradiation period indicates that the bacterium is deficient in an excision-repair system . These data suggest that P . haemolytica lacks some of the important mechanisms to repair UV-induced damage.

Avian Dis, 1991 Jul-Sep, 35(3), 618 - 20
Pasteurellosis in bobwhite quail; Bermudez AJ et al.; A flock of 5000 six-week-old bobwhite quails (Colinus virginianus) experienced high mortality (52%) over a 2-day period . Mortality was 99% within a 6-day period . Clinical signs were depression followed shortly by death . Gross lesions observed in dead quails were congested lungs and, in a few cases, mottled livers . Histopathologic examination revealed severe, diffuse, heterophilic interstitial pneumonia and multifocal areas of hepatic and splenic necrosis with numerous intracellular and extracellular short bacterial rods . Serotype 3, 4, 15, 16, Pasteurella multocida, isolated from the index case, caused 50% mortality in experimentally inoculated bobwhite quails within 9 to 24 hours . This report indicates that pasteurellosis can cause peracute disease in bobwhite quails with very high mortality.

Vet Pathol, 1991 Jul, 28(4), 275 - 85
Alterations in pulmonary morphology and peripheral coagulation profiles caused by intratracheal inoculation of live and ultraviolet light-killed Pasteurella haemolytica A1 in calves; Whiteley LO et al.; Eighteen male Holstein calves were divided into groups of three and inoculated intratracheally with 5 x 10(9) logarithmic phase or ultraviolet light-killed Pasteurella haemolytica biotype A serotype 1 . Serial coagulation profiles were done on one calf from each group during the first 24 hours after inoculation . One calf from each group was necropsied at 4, 12, and 24 hours after inoculation and lesions were characterized with light and transmission electron microscopy . We found that 1) the pulmonary intravascular macrophage may have an important role in the early intravascular inflammatory events; 2) there was morphologic evidence for local initiation of the coagulation cascade in the lung early in the disease process but it was not a consumptive process; and 3) killed-bacteria were capable of causing fibrin exudation, platelet aggregation and alveolar epithelial damage similar to live bacteria, but the degenerative changes in neutrophils, endothelial cells and intravascular fibrin formation that occur with live bacteria were not seen.

Vet Pathol, 1991 Jul, 28(4), 267 - 74
Colonization of the pharyngeal tonsil and respiratory tract of the gnotobiotic pig by a toxigenic strain of Pasteurella multocida type D; Ackermann MR et al.; Seven-day-old gnotobiotic pigs were inoculated intranasally with Pasteurella multocida and euthanatized 2, 5, 9, and 14 days after inoculation . Tissues from the oropharynx and respiratory tract of pigs were cultured quantitatively and analyzed microscopically . Pigs remained afebrile and alert, except one that died of acute fibrinopurulent pneumonia . Pasteurella multocida was isolated in greatest numbers from the pharyngeal tonsils, but only in low numbers from turbinate, trachea, lung, spleen, and liver . Significant histologic changes were limited to the tonsil . Infected pigs developed mild tonsillitis with lymphocytic hyperplasia, and accumulation of cell debris and bacteria in crypts . Capsular antigens of P . multocida, identified on tissue sections with rabbit anti-capsular polysaccharide antibody and immunocytochemical reagents, were confined to the crypt lumen . Ultrastructurally, bacteria were free within crypt material or within phagosomes of macrophages or neutrophils . In a second experiment, 5-day-old pigs were infected with Streptococcus suis type 2, followed by toxigenic Pasteurella multocida at 7 days of age; one pig died of streptococcal septicemia . Pigs developed a mild tonsillitis, and both bacteria were cultured from the tonsillar crypts for up to 14 days after infection . These studies show that a toxigenic strain of Pasteurella multocida, which is a causative agent of atrophic rhinitis, can colonize the tonsil and respiratory tract of gnotobiotic pigs for up to 14 days . In addition, colonization can occur concurrently with Streptococcus suis type 2.

Clin Ther, 1991 Jul-Aug, 13(4), 457 - 9
Treatment of posttraumatic osteitis with intravenous ofloxacin; Seibold R et al.; The subjects were 25 patients with osteomyelitis (n = 17) or other bone or joint infections, scheduled for surgical procedures, including debridement, sequestrectomy, and bone resection and reconstruction . Staphylococcus aureus was isolated in 22 patients, Staphylococcus epidermidis in one, Streptococcus haemolyticus in one, Pseudomonas aeruginosa in one, and a Pasteurella species in one . During surgery and for a mean of four days after surgery, each patient received 200 mg of ofloxacin intravenously twice daily (one patient received 300 mg and another received 400 mg twice daily) . The patients were then given 200 mg of ofloxacin orally twice daily until the wound was healed (after a mean of 18 days) . The wound was healed in all patients and no cases of reinfection occurred . It is concluded that intravenous ofloxacin given perioperatively may be more effective than oral ofloxacin in the management of osteomyelitis.

Zentralbl Veterinarmed B, 1991 Jul, 38(5), 345 - 52
Characterization of toxin from different strains of Pasteurella multocida serotype A and D; Frandsen PL et al.; Chromosomal DNA from 13 different selected Pasteurella multocida spp . multocida strains of serotypes A and D were isolated and compared . All 10 toxigenic strains were recognized by a DNA probe which included the toxA gene coding for the Pasteurella multocida toxin (PMT) . None of the three nontoxigenic strains reacted with the DNA probe . Toxin from the 10 toxigenic strains were isolated and compared . All were found to possess the biological characteristics previously described for the PMT isolated from P . multocida ssp . multocida NCTC 12178, including molecular mass of approx . 143 kDa and reactivity with a series of monoclonal antibodies . Toxin prepared from different toxigenic strains could not be differentiated immunologically by tandem crossed immunoelectrophoresis, Toxin, which was affinity purified from four of the strains and subsequently inactivated by formaldehyde, was cross-protective when used for vaccination of mice before challenge with PMT . It is concluded that the toxin from toxigenic strains of P . multocida ssp . multocida must be very similar, if not identical.

Lab Anim, 1991 Jul, 25(3), 236 - 41
Naturally acquired Pasteurella multocida subsp . multocida infection in a closed colony of rabbits: characteristics of isolates; Digiacomo RF et al.; Twelve litters, comprising 41 rabbits aged 35 to 60 days old, in a closed university colony, were monitored for acquisition of nasal Pasteurella multocida subsp . multocida infection . Isolates from 11 infected rabbits were characterized by colonial morphology, capsular type, biotype and antibiotic resistance . Selected isolates were further characterized by somatic antigen typing . Two major strains of P . multocida subsp . multocida were detected in the colony . One strain had mucoid colonies, fermented few carbohydrates and was serotype A:5, whereas, the other strain had smooth iridescent colonies, non-typeable capsular antigen, type 3 somatic antigen and fermented more than twice as many carbohydrates.

J Wildl Dis, 1991 Jul, 27(3), 367 - 95
Epizootiology of avian cholera in wildfowl; Botzler RG; Pasteurella multocida, the cause of avian cholera, has naturally infected over 100 species of free-living birds . Among wild birds, avian cholera has its greatest impact on North American wildfowl . Epizootics usually are explosive in onset and may involve thousands of birds . The disease has been reported in every month of the year among wildfowl . Disproportionate mortality, with some species suffering proportionately greater mortality than others, has been a common feature of this disease . Presence of animal organic matter plays a significant role in the survival of P . multocida . There are conflicting reports or a lack of information on the role of host sex, age, body size, other physical features, genetic variation or behavioral differences, as predisposing factors to infection by P . multocida . There also are ambiguities on the relationship between season, precipitation, temperature, nutritional stress, water quality, other microorganisms, and environmental contaminants, and the occurrence of avian cholera in wildfowl . Two competing hypotheses for the year-round reservoir of wildfowl strains of P . multocida are ambient soil or water of enzootic sites, and carrier animals; most current evidence favors the role of carrier animals . Transmission most likely occurs by ingestion of contaminated water, inhalation of bacteria-rich aerosols, or both . While many techniques have been proposed to prevent or control avian cholera, none have been rigorously tested to determine their effectiveness.

Br Vet J, 1991 Jul-Aug, 147(4), 352 - 5
Isolation of Pasteurella haemolytica from the nasal cavity of goats; Jasni S et al.; Twenty transport-stressed goats were divided into two groups . The first group was further stressed with steroid . Pasteurella haemolytica was found at various sites in the nasal cavity of goats in this group as early as 2 weeks post-transportation . The successful isolations continued consistently with more goats having pure growth of P . haemolytica at later stages . Mild catarrh rhinitis, loss of epithelial cilia and erosions were the main lesions observed in the nasal cavity . Goats in the second group that were not given steroid injections had inconsistent bacterial isolation and less severe pathological lesions.

Can J Vet Res, 1991 Jul, 55(3), 234 - 8
Naturally acquired Pasteurella multocida infection in rabbits: clinicopathological aspects; DiGiacomo RF et al.; A cohort of 41 New Zealand White rabbits, 35 to 60 days old, from twelve litters were followed for twelve weeks for development of pasteurellosis . Eleven of 19 rabbits in five litters acquired Pasteurella multocida infection . The incubation period was difficult to determine as P . multocida infection was detected both before and after the onset of rhinitis . The response of rabbits to infection varied from subclinical infection to death from systemic pasteurellosis . Atrophy of the maxilloturbinates of the nares was detected in rabbits with chronic rhinitis associated with P . multocida infection.

Can J Vet Res, 1991 Jul, 55(3), 224 - 8
Atrophic rhinitis caused by Pasteurella multocida type D: morphometric analysis; Martineau-Doize B et al.; In order to study the distribution and the extent of atrophy caused by Pasteurella multocida in the nasal conchae, experimental piglets were injected intramuscularly at seven days of age with either two or four 50% mouse lethal doses per kg body weight of P . multocida type D dermonecrotoxin . Experimental and control piglets were killed four, six and ten days postinjection . Serial transverse paraffin embedded sections of the noses were cut throughout the entire length of the nasal conchae . The area of the nasal ventral conchae was measured and the morphometric index of the nasal cavity was calculated . It was observed that P . multocida type D dermonecrotoxin induced severe atrophy of the nasal ventral conchae . This atrophy was present along the entire conchae . However, it was most severe at the level of the first and second premolar teeth.

J Infect, 1991 Jul, 23(1), 65 - 7
Pasteurella haemolytica endocarditis; Yaneza AL et al.; Although human infections with bacteraemia due to Pasteurella multocida are not uncommon, endocarditis associated with P . haemolytica is rare . We describe such a case in which the patient died despite treatment with apparently appropriate antimicrobial agents.

J Clin Microbiol, 1991 Jul, 29(7), 1328 - 32
Detection and enumeration of toxin-producing Pasteurella multocida with a colony-blot assay; Magyar T et al.; Colonies of toxin-producing Pasteurella multocida were detected with peroxidase-labeled monoclonal antibodies by a membrane assay . Examination of the specificity of the assay with 29 P . multocida cultures representing various geographic origins, hosts, and serotypes indicated that the test was specific for toxin-producing strains . No cross-reactions were observed with Bordetella species that can be associated with P . multocida in producing diseases in animals . A single membrane could be used to assay several isolated strains for toxin production or to enumerate toxin-producing colonies in mixed cultures . Toxin-producing P . multocida colonies were detected in primary cultures; hence, the assay appears to have good potential for widespread application with clinical samples.

J Laryngol Otol, 1991 Jul, 105(7), 571 - 2
Meningitis from canine Pasteurella multocida following mastoidectomy; Dammeijer PF et al.; A case of Pasteurella multocida meningitis, following a mastoidectomy is presented . The association of close contact with pets, many of which harbour Pasteurella multocida as part of their normal buccal flora . This case confirms the potential benefit of taking an ear swab prior to mastoid surgery and in seeking an appropriate 'pet' history.

Microb Pathog, 1991 Jul, 11(1), 47 - 56
Evidence for non-siderophore-mediated acquisition of transferrin-bound iron by Pasteurella multocida; Ogunnariwo JA et al.; Two clinical isolates of Pasteurella multocida associated with bovine pneumonia were examined for iron acquisition . Both isolates were capable of obtaining iron for growth from bovine but not from human, avian, equine or porcine transferrin . This correlated with specific binding of bovine transferrin by iron-limited cells or isolated membranes . No siderophore was detected in the strains by a general screening assay . In response to iron-limited conditions, a number of high molecular mass iron-regulated outer membrane proteins were produced including an 82 kDa receptor protein which was affinity isolated with biotinylated transferrin . In contrast, avian strains of P . multocida could not use transferrin-bound for growth and did not express either transferrin binding activity or the 82 kDa receptor protein.

Nature, 1991 Jun 27, 351(6329), 759 - 61
Activation of Escherichia coli prohaemolysin to the mature toxin by acyl carrier protein-dependent fatty acylation; Issartel JP et al.; Haemolysin secreted by pathogenic Escherichia coli binds to mammalian cell membranes, disrupting cellular activities and lysing cells by pore-formation . It is synthesized as nontoxic prohaemolysin (proHlyA), which is activated intracellularly by a mechanism dependent on the cosynthesized HlyC . Haemolysin is one of a family of membrane-targeted toxins, including the leukotoxins of Pasteurella and Actinobacillus and the bifunctional adenylate cyclase haemolysin of Bordetella pertussis, which require this protoxin activation 1-5 . HlyC alone cannot activate proHlyA, but requires a cytosolic activating factor6 . Here we report the cytosolic activating factor is identical to the acyl carrier protein and that activation to mature toxin is achieved by the transfer of a fatty acyl group from acyl carrier protein to proHlyA . Only acyl carrier protein, not acyl-CoA, can promote HlyC-directed proHlyA acylation, but a range of acyl groups are effective.

J Med Microbiol, 1991 Jun, 34(6), 333 - 7
Dermonecrotic toxin production by strains of Pasteurella multocida isolated from man; Donnio PY et al.; Ninety-four clinical isolates of Pasteurella multocida of human origin were tested for dermonecrotic toxin (DNT) production by three methods: dermonecrotic test in guinea-pigs, Vero cell culture cytotoxicity and ELISA . The strains were isolated from patients living in a rural area with widespread intensive pig breeding . Six strains were found to be toxigenic by the three tests . A major protein band of Mr 145 Kda corresponding to DNT on immunoblots was demonstrated in extracts from these strains . All were isolated from respiratory tract (diseases 5, healthy carriage 1) . The difference between isolates from the respiratory tract and isolates from wounds inflicted by pets was statistically significant with regard to DNT production (p less than 0.02) . A possible role of the toxin in pulmonary diseases caused by P . multocida has yet to be established.

Chest . 1991 Jun;99(6):1517.
Telescoping plugged catheter . An unusual way of diagnosing Pasteurella multocida pneumonia; Ruiz-Santana S et al.; We report a case of Pasteurella multocida pneumonia and its unusual clinical presentation . We also discuss the rarity of its diagnosis by TPC specimens and the delay in both an adequate diagnosis and treatment.

J Vet Pharmacol Ther, 1991 Jun, 14(2), 174 - 84
Effects of experimentally induced Pasteurella haemolytica infection in dairy calves on the pharmacokinetics of flumequine; Mevius DJ et al.; The effect of experimental Pasteurella haemolytica infection on the intravenous and intramuscular pharmacokinetics of flumequine was studied in dairy calves . The plasma concentration-time curve of flumequine after intravenous injection of 5 mg/kg bodyweight flumequine of a 10% solution before and after experimental infection, was best described by a three-compartment open model . After intramuscular injection of the same dosage rate of a 3% flumequine suspension is was best described by the one-compartment open model with first-order absorption . The experimental infection by intratracheal administration of infectious bovine rhinotracheitis (IBR)-virus and 5 days later intrapulmonary administration of Pasteurella haemolytica produced a clear temperature rise and signs of disease expressed as Average Health Status . Subsequently, plasma Fe and Zn concentration decreased after infection . The distribution volumes Vc, Vd(area) and Vd(ss) after infection (0.07 +/- 0.04, 1.38 +/- 0.36 and 0.50 +/- 0.11 l/kg, respectively) were smaller than those before infection, but the differences were not significant (P less than or equal to 0.1) . The intravenous AUC infinity was significantly increased (21.86 +/- 3.51 to 33.85 +/- 2.97 mg.h/l, P less than or equal to 0.01) and the total body clearance (ClB) significantly decreased (0.24 +/- 0.02 to 0.15 +/- 0.01, P less than or equal to 0.01) after infection . After intramuscular injection of flumequine at 5 mg/kg as a 3% suspension, only the bioavailability, F, was significantly decreased after infection (78.5 +/- 14.3 to 59.7 +/- 21.2%, P less than or equal to 0.02) . However, this had no consequences for the dosage regimen used . The urine concentration ratio flumequine:7-hydroxy-flumequine:conjugated flumequine changed from 2:1:10 before infection to 6:1:15 after infection, which indicates that hydroxylation and glucuronidation as metabolic pathways for flumequine were decreased after Pasteurella sp . infection.

Aust Vet J, 1991 Jun, 68(6), 201 - 3
Pasteurella multocida septicaemia in fallow deer (Dama dama); Carrigan MJ et al.; Thirteen of 100 fallow deer, aged between 6 months and 10 years, died over a 5 week period . The deaths occurred in 2 outbreaks 3 weeks apart . Both outbreaks were preceded by at least 3 days of cold wet and windy weather, and were associated with water-logged pastures . Affected animals were usually found dead, with a frothy blood-stained nasal discharge . In the 8 deer necropsied, gross lesions included widespread subserosal petechial haemorrhages, severe pulmonary congestion and oedema with froth-filled airways, and fibrinous pneumonia and pleurisy in 4 deer . Two deer, also, had extensive subcutaneous petechial and ecchymotic haemorrhages and oedema of skeletal musculature . Histologically, the most significant lesions were present in the lungs . Moderate to severe pulmonary congestion and oedema, with fibrinous exudation into alveoli and septal oedema, were present in all deer . In some deer these changes were accompanied by a diffuse infiltration with polymorphonuclear leucocytes . Pasteurella multocida was isolated from a range of tissues from 7 of 8 deer examined . The remaining animal had been treated with antibiotics 8 hours before death . The isolates had identical polyacrylamide gel electrophoresis patterns and were of the same antigenic type-Carter group A, Heddleston type 3,4.

Zentralbl Veterinarmed B, 1991 Jun, 38(4), 265 - 8
Toxigenic Pasteurella multocida in rabbits with naturally occurring atrophic rhinitis; Frymus T et al.; In a commercial rabbitry nasal swabs were taken from 36 animals with enzootic upper respiratory disease resembling porcine atrophic rhinitis . 35 Pasteurella multocida strains were isolated from 17 rabbits . Among 30 strains tested for dermonecrotic toxin production 3, derived from 3 animals, were positive in the guinea pig skin test . 15 Bordetella bronchiseptica strains were recovered from 14 rabbits . No toxigenic strains were found among 6 isolates tested using the same method.

Vet Microbiol, 1991 Jun, 28(1), 75 - 92
Relationship between the iron regulated outer membrane proteins and the outer membrane proteins of in vivo grown Pasteurella multocida; Choi-Kim K et al.; The SDS-PAGE patterns of the outer membrane protein (OMP) extracts of Pasteurella multocida strain P1059, grown under iron-restricted, iron-replete and in vivo conditions, were examined . The results showed that the iron-regulated outer membrane proteins (IROMPs) with molecular masses of 76 kDa, 84 kDa, and 94 kDa were expressed by bacteria grown in iron-restricted media . They were also expressed by in vivo grown P . multocida . Convalescent-phase sera, obtained from turkeys which had survived pasteurellosis, contained antibodies that reacted intensly with th three IROMPs . This indicated that these proteins were expressed in vivo . Bacteria expressing the IROMPs showed greater binding to Congo Red when compared to cells not expressing IROMPs . Cells expressing the IROMPs or its OMP extracts grown in iron-restricted media also showed greater binding to 59Fe-pasteurella siderophore (multocidin) when compared to bacteria or its extracts not expressing IROMPs . Convalescent-phase sera, which contained antibodies against the IROMPs, blocked this specific 59Fe-multocidin binding to IROMPs . Autoradiography was used to determine which of these IROMPs functioned as a receptor for the iron-multocidin complex . The results suggested that these three IROMPs have specific epitopes for binding to the iron multocidin complex.

Vet Microbiol, 1991 Jun, 28(1), 61 - 73
Immunological properties of Actinobacillus pleuropneumoniae hemolysin I; Frey J et al.; The 105 kDa hemolysin I protein from Actinobacillus pleuropneumoniae serotype I type strain 4074 (HlyI) was shown by immunoblot analysis to be the predominant immunogenic protein if convalescent field sera or sera from pigs experimentally infected with A . pleuropneumoniae serotype 1 were used . SDS gel- and immunoblot-analysis using total culture, washed cells or culture supernatant showed that HlyI is essentially secreted and is not found attached to the bacteria . Proteins in the 105 kDa range that react strongly with anti-HlyI antibody, are produced by all serotypes and are presumed to be their hemolysins . Sera from pigs experimentally infected with each of the 12 serotypes strongly reacted with HlyI . In addition, some sera from pigs that were confirmed to be negative for A . pleuropneumoniae, also reacted with HlyI as well as with related proteins from Actinobacillus rossii and Actinobacillus suis . These two species produce proteins in the 105 kDa range which cross-react strongly with HlyI . They could be the source of the immunological reactions of the A . pleuropneumoniae-negative sera with HlyI . However, no cross-reactions could be found between HlyI and the Pasteurella haemolytica leukotoxin, the Escherichia coli alpha-hemolysin or related proteins from various hemolytic E . coli strains isolated from pigs . The immunological cross-reactions of HlyI with related proteins from A . rossii, A . suis and possibly from other bacterial species may create uncertainty in interpretation if HlyI is used as the antigen in serodiagnosis of A . pleuropneumoniae.

J Clin Microbiol, 1991 Jun, 29(6), 1183 - 7
Construction of a DNA probe and detection of Actinobacillus pleuropneumoniae by using polymerase chain reaction; Sirois M et al.; A 1.5-kb Actinobacillus pleuropneumoniae 4074 DNA fragment from a genomic library was found to hybridization . No cross-hybridization hybridization . No cross-hybridization was detected with DNAs from hemolytic members of the family Pasteurellaceae . From the nucleotide sequence of the putative genomic probe, three primers were synthesized for use in polymerase chain reactions (PCRs), with 31 strains tested by using purified and crude DNA targets . PCR amplification products of 610 and 985 bp were observed in nucleic acids extracted from the 12 known serotypes and a biotype 2 strain . Template DNAs from other gram-negative and gram-positive bacteria, some of them found in the normal flora of swine and the upper respiratory tract, were not amplified by PCR . The only exception was an amplification of a similar 610- or 985-bp sequence in Actinobacillus lignieresii, a species that is closely related to A . pleuropneumoniae but that has never been isolated from swine . Amplification of specific A . pleuropneumoniae sequences by PCR directly from clinical specimens may find applications in the identification of asymptomatic carriers as well as in efforts to eradicate porcine pleuropneumonia.

Zentralbl Veterinarmed B, 1991 Jun, 38(4), 306 - 14
ISCOM of BHV-1 envelope glycoproteins protected calves against both disease and infection; Merza M et al.; A subunit vaccine in the form of immunostimulating complex (iscom) was prepared to contain the envelope glycoproteins of bovine herpesvirus type 1 (BHV-1) . This iscom preparation was tested in a vaccination experiment on 4-month-old calves seronegative to BHV-1 . In this experiment, four groups with three animals per group were used . Two groups were vaccinated with the iscom preparation twice, four weeks apart, one group with 50 micrograms and the other with 100 micrograms per calf . The third group received a commercial inactivated whole-virus vaccine applying the same vaccination program . The fourth group served as control . Two weeks after the second vaccination, all the animals were challenge-infected intranasally with a virulent BHV-1 strain and four days later with a virulent Pasteurella multocida--this in order to mimic hard field conditions . When exposed to challenge infection, all the animals vaccinated with the iscom were fully protected, i.e., no virus could be recovered from their nasal secretions and no clinical symptoms were recorded . In contrast, the animals vaccinated with the commercial vaccine, responded to challenge with moderate fever and loss of appetite, and virus was isolated from the nasal secretions . The animals in the control group developed severe clinical symptoms . In the sera of iscom-vaccinated animals, the virus neutralization titers reached levels of 1/3500 or higher.

Am J Pathol, 1991 May, 138(5), 1191 - 8
The role of leukocytes in the pathogenesis of fibrin deposition in bovine acute lung injury; Car BD et al.; The peculiarly fibrinous nature of bovine acute lung injury due to infection with Pasteurella haemolytica A1 suggests an imbalance between leukocyte-directed procoagulant and profibrinolytic influences in the inflamed bovine lung . Calves with experimental pneumonia produced by intratracheal inoculation with P . haemolytica A1 developed acute locally extensive cranioventral fibrinopurulent bronchopneumonia . Pulmonary alveolar macrophages (PAM) recovered by segmental lavage from affected lung lobes were 30 times more procoagulant than PAM obtained from unaffected lung lobes and 37-fold more procoagulant than PAM from control calf lungs . Unlike the enhancement of procoagulant activity, profibrinolytic activity (plasminogen activator amidolysis) of total lung leukocytes (PAM and plasminogen activator neutrophils {PMN}) was decreased 23 times in cells obtained from affected lung lobes and also was decreased four times in cells obtained from unaffected lobes of infected animals . This marked imbalance in cellular procoagulant and fibrinolytic activity probably contributes significantly to enhanced fibrin deposition and retarded fibrin removal . In addition, PAM from inflamed lungs were strongly positive for bovine tissue factor antigen as demonstrated by immunocytochemistry . Intensely tissue factor-positive PAM enmeshed in fibrinocellular exudates and positive alveolar walls were situated such that they were likely to have, in concert, initiated extrinsic activation of coagulation in the acutely inflamed lung . These data collectively suggest that enhanced PAM-directed procoagulant activity and diminished PAM- and PMN-directed profibrinolytic activity represent important modifications of local leukocyte function in bovine acute lung injury that are central to the pathogenesis of lesion development with extensive fibrin deposition and retarded fibrin removal.

Vet Microbiol, 1991 May, 27(3-4), 309 - 26
Haemorrhagic septicaemia: correlation of vaccinal antibody responses in mice with protection against Pasteurella multocida strain M1404; Dawkins HJ et al.; This study examined the protection induced by oil adjuvant vaccine and broth bacterin in mice . Protective immunity was induced by both oil adjuvant and bacterin vaccination procedures . Oil adjuvant vaccination induced a 10(5)-fold increase for lethal challenge over control mice, while secondary vaccination induced a further 10-fold increase in resistance to lethal challenge . Broth bacterin induced a slightly weaker protective response with 10(4)- and 10(5)-fold increases in resistance to lethal challenge following primary and secondary vaccination, respectively . There was a significant relationship between IgG antibody levels and resistance to challenge (P = 0.026) . Protection lasted for at least 20 weeks after a primary oil adjuvant vaccination . There was also a strong and significant relationship between IgG antibody levels and the passive protection afforded by serum transfer in each experiment within this study and the overall correlation was highly significant (P = 0.00001) . There appeared to be a relationship between protection and the antibody response to major protein bands with the apparent molecular mass Mr . 94,000; 80,000; 67,000; 35,000 and 32,000 as well as to the bands in the region of the lipopolysaccharide components of P . multocida (approximately Mr, 14-15,000) . Whether protection resulted from recognition of specific antigens or was a result of both antibody levels and antibody specificity remains to be defined.

Zentralbl Veterinarmed A, 1991 May, 38(4), 287 - 99
Statistical evidence for a link between bronchopneumonia and disseminated focal nephritis in pigs; Buttenschon J; An investigation on the occurrence of different pneumonia types and their possible concurrence with other pluck organ disorders was made on 6,565 pigs presented at slaughter . The frequency of disseminated focal nephritis in a bronchopneumonia group and a non-bronchopneumonia residual group, respectively, was found to differ significantly from the mean frequency of nephritis in all pig plucks examined . The number of lesioned kidneys in each of 28 samples contributing to the bronchopneumonia group and in each of 8 samples contributing to the residual group was regressed group-wise on the number of individual plucks examined in each sample; the correlation coefficient for each of these two groups was calculated . These calculations showed a highly significant link between bronchopneumonia and disseminated focal nephritis . The histopathological and bacteriological examination of some lung and kidney lesions representing the bronchopneumonia group substantiated this finding . It is concluded that the two diseases are connected through dissemination, and that Pasteurella multocida is the organism involved in the majority of cases.

J Gen Microbiol, 1991 May, 137 ( Pt 5), 1067 - 71
Ultrastructural localization of the Pasteurella multocida toxin in a toxin-producing strain; iDali C et al.; Toxigenic strains of Pasteurella multocida produce the 147 kDa protein Pasteurella multocida toxin (PMT) which is responsible for the osteoclastic bone resorption in progressive atrophic rhinitis in pigs and induces such resorption in all experimental animals tested so far . In the present study we have carried out immunocytochemistry on formaldehyde- and glutaraldehyde-fixed ultracryocut P . multocida using a pool of monoclonal antibodies against different epitopes on PMT as the first layer and affinity purified rabbit anti-mouse IgG as the second layer . Goat anti-rabbit IgG conjugated with 5 nm gold particles was used as marker . The gold particles were silver-enhanced prior to examination in the transmission electron microscope . Whole bacteria were also immunostained after fixation and critical point drying and examined by scanning transmission electron microscopy . The results showed that PMT was located in the cytoplasm of P . multocida . PMT could not be detected on intact, undamaged P . multocida by scanning electron microscopy . Neither pili nor flagella could be detected on the surface of the negatively stained P . multocida strains investigated . PMT has a series of characteristics encompassed in the definition of an exotoxin . However, that PMT was not secreted by living intact P . multocida is unexpected for an exotoxin.

Microb Pathog, 1991 May, 10(5), 411 - 7
Neutralizing monoclonal antibodies to Pasteurella haemolytica leukotoxin affinity-purify the toxin from crude culture supernatants; Gentry MJ et al.; The leukotoxin of Pasteurella haemolytica is a major virulence factor of the organism . It is an unstable protein which has proven very difficult to purify using traditional techniques . Hybridomas secreting monoclonal antibodies (mAbs) to P . haemolytica leukotoxin were derived from spleen cells of a mouse immunized with crude culture supernatant . Five hybridomas secreting mAbs specific for the leukotoxin were stabilized . Each of the mAbs reacted with a protein of approximately 100 kDa in toxic culture supernatants, and two of them completely neutralized the toxin in vitro . Affinity chromatography of crude culture supernatant on a column prepared with one of the neutralizing mAbs resulted in the isolation of biologically active toxin.

Res Vet Sci, 1991 May, 50(3), 368 - 70
Evidence of phenotypic dichotomy within an individual Pasteurella multocida type strain and among some haemorrhagic septicaemia-causing field isolates; Dawkins HJ et al.; Haemorrhagic septicaemia-causing strains of Pasteurella multocida were identified by a disease-specific ELISA . Some strains, however, were of the same serotype as those which cause haemorrhagic septicaemia (HS) but were negative when tested in the disease specific ELISA . The suspect false negative isolates were passaged in mice and retested in the HS ELISA with the same result . Immunoelectron microscopy was used to examine further these suspect HS-causing strains . Monoclonal antibodies and protein A-gold showed that the suspect negative organisms were a mixture of phenotypes with less than 10 per cent, and usually less than 2 per cent, of the population expressing HS-associated epitopes . The degree of staining on the organisms expressing the HS-epitopes was of the same intensity as the positive control organism . Expression of the HS-associated epitopes is presumably too low to allow detection in the current HS ELISA.

J Wildl Dis, 1991 Apr, 27(2), 296 - 316
Chronic upper respiratory tract disease of free-ranging desert tortoises (Xerobates agassizii); Jacobson ER et al.; Seventeen desert tortoises, Xerobates agassizii, with upper respiratory tract disease were examined; thirteen were euthanatized for necropsy . Four normal control desert tortoises from a clinically healthy population were similarly evaluated . Hemoglobin and phosphorus values were significantly (P less than or equal to 0.05) lower and serum sodium, urea, SGOT, and cholesterol values were significantly higher in ill tortoises compared to controls . No significant differences in concentrations of serum or liver vitamins A and E were found between the two groups . While no significant differences were found for concentrations of lead, copper, cadmium, and selenium, the livers of ill tortoises had higher concentrations of mercury and iron . Lesions were found consistently in the upper respiratory tract (URT) of ill tortoises . In all ill tortoises dense infiltrates of lymphocytes and histiocytes obscured the mucosal epithelium and underlying glands . The mucosal epithelium was variably dysplastic, hyperplastic, and occasionally ulcerated . Electron microscopic studies revealed small (350 to 900 nm), pleomorphic organisms resembling Mycoplasma sp., in close association with the surface epithelium of the URT of ill tortoises . Pasteurella testudinis was cultured from the nasal cavity of all ill tortoises and one of four control tortoises . A Mycoplasma sp . was cultured from the nasal passageways of four ill tortoises and was ultrastructurally similar to the pleomorphic organism present on the mucosa in tissue section.

Vet Microbiol, 1991 Apr, 27(2), 169 - 74
Immunity induced in rats vaccinated with toxoid prepared from heat-labile toxin produced by Pasteurella multocida serogroup D; Thurston JR et al.; Rats were vaccinated with a toxoid (D-toxoid) prepared from purified heat-labile toxin (D-toxin) produced by Pasteurella multocida serogroup D . Vaccination of rats with D-toxoid prevented death and other effects of D-toxin (hepatic necrosis, development of elevated leukocyte counts, lymphopenia, neutrophilia, and elevated complement titers) that occurred in phosphate buffered saline (PBS)-vaccinated control rats.

J Comp Pathol, 1991 Apr, 104(3), 233 - 43
Experimental pneumonia in mice produced by combined administration of Bordetella parapertussis and Pasteurella haemolytica isolated from sheep; Jian Z et al.; One-hundred-and-thirty-seven, 3-week-old, Swiss mice were inoculated intranasally with Bordetella parapertussis and Pasteurella haemolytica which had been isolated from naturally occurring cases of chronic non-progressive pneumonia in sheep . The combined administration produced a significantly more severe bronchopneumonia which occurred earlier, persisted for a longer period and involved a higher percentage of mice than that which was produced with B . parapertussis or P . haemolytica alone . These findings demonstrate an additive or synergic action between the two agents or their metabolic products, and provide indirect evidence that such interaction may occur in ovine chronic non-progressive pneumonia.

Infect Immun, 1991 Apr, 59(4), 1470 - 5
Antibodies to outer membrane proteins but not to lipopolysaccharide inhibit pulmonary proliferation of Pasteurella multocida in mice; Lu YS et al.; The role of rabbit antibodies against Pasteurella multocida outer membrane proteins and lipopolysaccharides (LPS) in resistance remains unknown . Pooled immune sera against P . multocida outer membranes were prepared from specific-pathogen-free rabbits immunized with sucrose gradient-purified P . multocida outer membranes . Western immunoblotting showed that purified outer membrane protein antibodies reacted strongly against the outer membrane proteins but not the purified LPS . Affinity-purified LPS antibodies exhibited strong reactivity against purified LPS and very little reactivity against outer membrane vesicles . Mice were inoculated intranasally with immune serum or normal rabbit serum, challenged intranasally with 10(6) CFU of P . multocida, and euthanatized 48 h later to determine the number of P . multocida organisms in the lungs . Mice inoculated with pooled immune serum had a 3,300-fold reduction (P less than 0.001) in the numbers of P . multocida in the lungs as compared with the controls . Similarly, mice inoculated with purified outer membrane protein antibodies had a 201-fold reduction (P less than 0.001) in the numbers of P . multocida . Conversely, mice inoculated with affinity-purified LPS antibodies had a 1.1-fold reduction (P greater than 0.50) in the numbers of P . multocida . These results show that antibodies against the outer membrane proteins but not the LPS are the components of rabbit immune sera which inhibit P . multocida proliferation in mouse lungs.

J Vet Diagn Invest, 1991 Apr, 3(2), 124 - 6
In vitro antimicrobial susceptibility of Pasteurella haemolytica and Pasteurella multocida recovered from cattle with bovine respiratory disease complex; Post KW et al.; The antimicrobial susceptibilities of 421 Pasteurella haemolytica and 158 P . multocida isolates recovered from cattle with respiratory disease were determined with a microdilution minimal inhibitory concentration test system . Isolates were analyzed for patterns of resistance to ampicillin, ceftiofur, erythromycin, gentamicin, penicillin, spectinomycin, sulfachlorpyridazine, sulfadimethoxine, tetracycline, and tylosin . All isolates tested were found susceptible to ceftiofur and sulfachlorpyridazine . Pasteurella haemolytica isolates were resistant to ampicillin, penicillin, sulfadimethoxine, tetracycline, and tylosin . Pasteurella multocida isolates were resistant to sulfadimethoxine, tetracycline, and tylosin.

Vet Immunol Immunopathol, 1991 Apr, 28(2), 157 - 63
Pasteurella haemolytica A1 purified capsular polysaccharide does not stimulate interleukin-1 and tumor necrosis factor release by bovine monocytes and alveolar macrophages; Czuprynski CJ et al.; Purified capsular polysaccharide (CPS) stimulated significant release of interleukin-1 (IL-1) activity from bovine blood monocytes but not alveolar macrophages in vitro . The ability of CPS to induce IL-1 release was resistant to boiling and inhibited by the addition of polymyxin beta . Thus, it is likely that the IL-1 release stimulated by CPS resulted from the small amount of contaminating lipopolysaccharide (LPS) that was present (an estimated 5 pg LPS per microgram CPS) rather than to a direct effect of CPS . Tumor necrosis factor activity was not detected in the culture supernatants of bovine monocytes incubated with purified CPS for 1-18 h in vitro.

Avian Dis, 1991 Apr-Jun, 35(2), 392 - 6
In vivo antigen expression by Pasteurella multocida; Glisson JR et al.; Pasteurella multocida was purified from the blood of turkeys affected with acute fowl cholera, and membrane preparations from those bacteria were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and visualized on immunoblots . Antigens were detected in the membranes of these in vivo-propagated bacteria that were not detected in membrane preparations of the same P . multocida strain grown in vitro . The unique antigens were detected in the detergent-insoluble phase and were enriched to various degrees by different detergents.

Avian Dis, 1991 Apr-Jun, 35(2), 251 - 6
Comparison of live avirulent M-9, Minnesota, and CU fowl cholera vaccines; Friedlander RC et al.; The M-9 and Minnesota (MN) avirulent Pasteurella multocida vaccines were evaluated and compared with the Clemson University (CU) vaccine, which had been shown to be highly effective in preventing fowl cholera in turkeys . Neither the M-9 nor the MN vaccine given in the drinking water was as effective as the CU vaccine in protecting turkeys against challenge with virulent P . multocida . When grown in brain-heart infusion (BHI) agar as recommended, the M-9 was not as efficacious as when it was grown in BHI broth . The M-9 was as effective as the CU vaccine only when grown in BHI broth and given at 10 times the standard dosage . Injection of the M-9 vaccine into the air spaces of the head at a site near the caudal rim of the ear after one vaccination in the drinking water was not as effective for hyperimmunizing potential breeders as was the CU vaccine injected at the same site . A microtiter agglutination test demonstrated a significant (P less than 0.05) correlation between the level of anti-P . multocida antibody found 1 week after vaccination and survival after challenge with virulent P . multocida.

Can J Vet Res, 1991 Apr, 55(2), 128 - 38
Vaccination against progressive atrophic rhinitis with a recombinant Pasteurella multocida toxin derivative; Nielsen JP et al.; Vaccination against progressive atrophic rhinitis using a purified recombinant derivative of the Pasteurella multocida toxin (PMT), was carried out . Ten pregnant gilts were vaccinated twice with the nontoxic derivative (dO) which apart from a lack of 121 amino acids had an amino acid sequence identical to PMT, while seven gilts were vaccinated with a purified, formaldehyde treated, native PMT and ten gilts served as non-vaccinated controls . The resulting piglets were inoculated intranasally with Bordetella bronchiseptica and toxigenic P . multocida . Among piglets from the nonvaccinated gilts all except one developed clinical atrophic rhinitis and 90% developed severe turbinate atrophy while only a few pigs in the vaccinated groups developed clinical or pathological signs of disease . Gilt colostra from the two vaccinated groups had similar mean anti-PMT titers and the mean titers in the offspring's sera from these groups were nearly identical throughout the study . No pigs born from unvaccinated gilts were seropositive until 8 wk of age (7 wk post-challenge) but 23% became seropositive at slaughter . The infection rate with toxigenic P . multocida in piglets and the total number of P . multocida colonies cultured from nasal swabs were significantly reduced at 5 wk and 8 wk of age in the vaccinated groups, when compared to controls . There was a significantly improved weight gain (greater than 9%) from birth to slaughter in offspring from vaccinated gilts . No significant differences in feed conversion rate or % lean meat were observed among the groups . The study showed the excellent immunoprotective properties of the nontoxic derivative of the PMT molecule.

Vet Microbiol, 1991 Apr, 27(2), 175 - 85
Proteins and antigens of Pasteurella multocida serotype 1 from fowl cholera; Ireland L et al.; The protein profiles of Pasteurella multocida serotype 1 isolates and the response of chickens to serotype 1 antigens were investigated using SDS-PAGE . Patterns obtained with Coomassie blue staining of soluble protein extracts were similar . The major difference between isolates was the position of one of the major proteins in the 34-38 kDa region . When chickens were experimentally infected with a clinical isolate of P . multocida serotype 1 various proteins were recognised by immunoblotting, including one with a relative molecular weight of 34 kDa; however, no reactions were observed in the region where LPS is known to migrate . When these infection sera were used in an EIA with purified LPS obtained from Heddleston serotype 1 type strain (X-73) they reacted strongly . Serum used for serotyping isolates in the gel diffusion precipitin test recognised many antigens in common with sera from infected birds, but some antigens were specific to typing sera.

Lab Anim Sci, 1991 Apr, 41(2), 162 - 5
An enzyme-linked immunosorbent assay for detection of chronic subclinical Pasteurella pneumotropica infection in mice; Manning PJ et al.; Serum samples from seventy-five, 3- to 12-week-old and 16 retired breeder male Swiss mice from a conventional colony with enzootic chronic subclinical Pasteurella pneumotropica infection were tested by enzyme-linked immunosorbent assay (ELISA) and Western blots for IgG antibodies to whole cell (WC) and lipooligosaccharide (LOS) antigens of P . pneumotropica . In 3- to 12-week-old mice, serum antibody levels to LOS exceeded those to the WC preparation . Western blots of sera from mice in this age group substantiated that a major component of the early IgG antibody response was directed against LOS antigens . Higher antibody levels to both antigen preparations in 3-week-old mice compared to mice 4 and 6 weeks old were interpreted as reflecting a decline in antibodies acquired from the dam . Active immunity indicative of infection was first detected at 8 weeks of age . Serum samples from retired breeder mice (28 weeks of age) also had substantial antibody titers to LOS but, in contrast to sera from mice in the younger age groups, retired breeders had significantly greater IgG reactivity to WC preparations than to LOS antigens . The superior specificity of the LOS antigen compared to the WC preparation in the ELISA was demonstrated by testing serum samples from retired breeder mice against WC and LOS antigens from P . ureae, P . multocida, and P . hemolytica . The reactivity of IgG against LOS antigens from these organisms was negligible, whereas substantial titers were evident to WC antigens . This ELISA, using LOS preparations as antigen, is a useful serologic assay for the detection of subclinical P . pneumotropica infection in mice.

Vet Microbiol, 1991 Apr, 27(2), 159 - 68
Lymphocyte subpopulations in peripheral blood of lambs experimentally infected with Pasteurella haemolytica; Sharma R et al.; The lymphocyte subpopulations in peripheral blood obtained from eleven lambs experimentally infected with Pasteurella haemolytica were compared with those obtained from eight control lambs by flow cytometry, using a panel of monoclonal antibodies against specific lymphocyte epitopes . Experimental infection with P . haemolytica was characterized by a transient but significant reduction in SBU-T1+ (CD5+) T cells and SBU-T4+ (CD4+ or helper) T lymphocytes (P less than 0.05) and a significant rise in lymphocytes which did not express the LCA p220 epitope and the pan T cell surface marker (CD5-LCA p220-) ("null") . The reductions in CD5+ and CD4+ lymphocytes occurred 24 h after experimental infection, returning to preinoculation levels 5 days post inoculation (DPI) . Five to 9 days after experimental infection, there was a significant increase in the number of lymphocytes, which expresses the pan T cell surface marker (CD5+) but which were CD4-CD8- . Lymphocyte transformation responses to the mitogen phytohaemagglutinin (PHA) were significantly reduced 24 h after experimental infection with P . haemolytica (P less than 0.05).

Infect Immun, 1991 Apr, 59(4), 1387 - 93
Recombinant derivatives of Pasteurella multocida toxin: candidates for a vaccine against progressive atrophic rhinitis; Petersen SK et al.; Potential vaccine components for protection against atrophic rhinitis in pigs were developed . This was achieved by deletion mutagenesis of the gene encoding the Pasteurella multocida toxin . Four purified toxin derivatives lacking different and widely separated regions in the amino acid sequence were characterized by a lack of toxic activity . One such component was shown to induce efficient protection of vaccinated female mice and their offspring against challenge with purified P . multocida toxin.

Lab Anim Sci, 1991 Apr, 41(2), 151 - 6
Heat-labile toxin-producing isolates of Pasteurella multocida from rabbits; Suckow MA et al.; Five of one hundred forty seven isolates of Pasteurella multocida from rabbits were found to produce heat-labile toxin . Each isolate was assayed for the ability of potassium thiocyanate (KSCN) extracts to cause dermonecrosis in guinea pig skin, ability of bacteria or filtrates to cause cytotoxicity in cell cultures, and reactivity with monoclonal antibodies to heat-labile P . multocida toxin . Five capsular type D isolates produced dermonecrosis and reacted with monoclonal antibodies to toxin . Filtrates of all five of these isolates were cytotoxic for cell cultures . Potassium thiocyanate extracts of all five isolates caused pleuritis and pneumonia in rabbits after intranasal inoculation . Turbinate atrophy was seen in 5 of 19 rabbits inoculated intranasally with toxic extracts . Heat-labile toxin was not produced by 109 capsular type A isolates or 19 nontypable isolates.

J Am Vet Med Assoc, 1991 Mar 15, 198(6), 1052 - 6
Development of pneumonia in desert bighorn sheep after exposure to a flock of exotic wild and domestic sheep; Callan RJ et al.; From 1986 to 1989, 5 desert bighorn sheep (3 Ovis canadensis mexicana and 2 O c nelsoni), ranging in age from 2 to 3 years, were exposed to a flock of exotic wild and domestic sheep to potentially achieve naturally acquired pneumonia . Pasteurella multocida was isolated from nasal samples from 4 of 6 sheep randomly sampled from the flock . Bighorn sheep were exposed individually and each exposure period was a trial . Treatment before and after exposure varied and included combinations of alpha interferon, antibiotics, anti-inflammatory drugs, and vaccines . Treatments were chosen on the basis of recommendations of others for treating pneumonia in desert bighorn sheep as well as our own experience in sheep and cattle . Regardless of treatment used, bighorn sheep in trials 1 to 4 developed signs of pneumonia within 10 to 14 days of exposure . Bighorn sheep in trials 1 to 3 died within 11 to 17 days of initial exposure . In trial 4, the bighorn sheep was isolated from the carrier sheep for treatment of pneumonia on day 14 and died on day 30 . Pasteurella multocida was isolated from lung tissue in 3 of the 4 bighorn sheep . On the basis of results of trials 1 to 4, a more in depth clinical study was conducted in trial 5 . Nasal and blood specimens were collected prior to and during trial 5 for bacteriologic culturing and serologic testing for bovine viral diarrhea virus, infectious bovine rhinotracheitis, parainfluenza-3 virus, and respiratory syncytial virus.(ABSTRACT TRUNCATED AT 250 WORDS)

J Biol Chem, 1991 Mar 15, 266(8), 4840 - 7
Pasteurella multocida toxin, a potent mitogen, increases inositol 1,4,5-trisphosphate and mobilizes Ca2+ in Swiss 3T3 cells; Staddon JM et al.; Pasteurella multocida toxin, both native and recombinant, is an extremely potent mitogen for Swiss 3T3 cells and acts to enhance the formation of total inositol phosphates (Rozengurt, E., Higgins, T., Changer, N., Lax, A.J., and Staddon, J.M . (1990) Proc . Natl . Acad . Sci . U.S.A . 87, 123-127) . P . multocida toxin also stimulates diacylglycerol production and activates protein kinase C (Staddon, J.M., Chanter, N., Lax, A.J., Higgins, T.E., and Rozengurt, E . (1990) J . Biol . Chem . 265, 11841-11848) . Here we analyze, by {3H}inositol labeling and high performance liquid chromatography, the inositol phosphates in recombinant P . multocida toxin-treated cells . Recombinant P . multocida toxin stimulated increases in {3H}inositol 1,4,5-trisphosphate ({3H}Ins(1,4,5)P3) and its metabolic products, including Ins(1,3,4,5)P4, Ins(1,3,4)P3, Ins(1,4)P2, Ins(4/5)P, and Ins(1/3)P . The profile of the increase in the cellular content of these distinct inositol phosphates was very similar to that elicited by bombesin . Furthermore, recombinant P . multocida toxin, like bombesin, mobilizes an intracellular pool of Ca2+ . Recombinant P . multocida toxin pretreatment greatly reduces the Ca2(+)-mobilizing action of bombesin, consistent with Ca2+ mobilization from a common pool by the two agents . The enhancement of inositol phosphates and mobilization of Ca2+ by recombinant P . multocida toxin were blocked by the lysosomotrophic agents methylamine, ammonium chloride, and chloroquine and occurred after a dose-dependent lag period . The stimulation of inositol phosphate production by recombinant P . multocida toxin persisted after removal of extracellular toxin, in contrast to the reversibility of the action of bombesin . Recombinant P . multocida toxin, unlike bombesin and guanosine 5'-O-(gamma-thiotriphosphate), did not cause the release of inositol phosphates in permeabilized cells . These data demonstrate that recombinant P . multocida toxin, acting intracellularly, stimulates the phospholipase C-mediated hydrolysis of phosphatidylinositol 4,5-bisphosphate.

Vet Microbiol, 1991 Mar, 27(1), 63 - 78
Cloning and expression of a 30 kDa surface antigen of Pasteurella haemolytica; Craven RC et al.; Pasteurella haemolytica biotype A serotype 1 is the principal etiologic agent of bovine pneumonic pasteurellosis . A clear understanding of the pathogenesis of this disease and the mechanisms of resistance to it has been limited by a lack of information on the important antigens of the organisms . Using recombinant DNA techniques we have cloned a segment of DNA from P . haemolytica A1 that encodes three proteins of 28, 30, and 32 kDa . Two of these proteins, 30 and 28 kDa, react strongly on a Western blot with a bovine serum raised against live cells of P . haemolytica A1 . The gene for the 30 kDa protein was localized to a 3.1 kbp EcoRI fragment, and expression of the 30 kDa protein was found to be independent of an E . coli promoter . The 30 kDa protein comigrated with a 30 kDa P . haemolytica protein that was susceptible to radioiodination and presumably exposed on the bacterial cell surface . The other principal radiolabeled P . haemolytica proteins were 100, 45, and 15 kDa . Antibodies against the 30 kDa protein, isolated from E . coli carrying the recombinant plasmid, recognized 30 kDa and 15 kDa proteins in P . haemolytica serotypes 1-15 and caused agglutination of whole P . haemolytica A1 cells . Cattle vaccinated with live P . haemolytica, P . haemolytica outer membrane proteins, or the cloned 30 kDa protein developed antibodies to the cloned 30 kDa protein as detected by Western blotting and densitometry . Sera were obtained from cattle vaccinated with live or killed P . haemolytica or saline and challenged with P . haemolytica . Those sera were evaluated for antibody responses to the cloned 30 kDa protein . High antibody responses to the 30 kDa protein significantly correlated (P less than 0.01) with resistance to challenge . From these studies it is concluded that the 30 kDa protein represents a surface antigen of P . haemolytica A1 that may be important in inducing immunity to P . haemolytica.

Am J Vet Res, 1991 Mar, 52(3), 453 - 7
Lysis of bovine platelets by Pasteurella haemolytica leukotoxin; Clinkenbeard KD et al.; Pasteurella haemolytica A1 culture supernatants caused rapid cytolysis (less than 5 minutes) of isolated bovine platelets as measured by leakage of the cytoplasmic enzyme lactate dehydrogenase (LD) . The platelet lytic factor had several features similar to P haemolytica leukotoxin . Like P haemolytica leukotoxin, the platelet lytic factor was produced by P haemolytica during logarithmic growth phase, was heat-labile, and was active against target cells (platelets) from ruminant species (cattle and sheep), but not from non-ruminant species (horses, pigs, and human beings) . Additionally, the platelet lytic factor was neutralized with antileukotoxin rabbit serum . The amount of LD leaked by a fixed concentration of bovine platelets was proportional to the amount of toxin added at low toxic doses and became maximal at 88 +/- 11% of the total platelet LD activity for high doses of toxin . When a fixed dose of toxin was used and the platelet concentration was varied, LD leakage was initially proportional to the platelet concentration, but plateaued at higher platelet concentrations . The platelet lytic factor required Ca2+ and was inhibited by addition of the Ca2+ chelator ethylene glycol-bis(beta-aminoethyl ether)N,N,N',N'-tetraacetic acid . Toxin-mediated platelet damage may be important in thrombi formation and fibrin exudation typically associated with P haemolytica pleuropneumonia of cattle.

APMIS, 1991 Mar, 99(3), 291 - 4
Isolation of Pasteurella caballi from an infected wound on a veterinary surgeon; Bisgaard M et al.; Comparison of phenotypical characters obtained from the type strain of Pasteurella caballi and a previously unclassified P.sp., isolated from an infected wound on a veterinary surgeon, allowed classification of the P.sp . with P . caballi . The P.sp . was isolated in a mixed culture with Escherichia coli and probably represents the first human isolate of P . caballi.

Vet Microbiol, 1991 Feb 15, 26(4), 349 - 58
Interaction of bovine alveolar macrophages with Pasteurella haemolytica A1 in vitro: modulation by purified capsular polysaccharide; Czuprynski CJ et al.; Preincubation of bovine alveolar macrophages with Pasteurella haemolytica A1 purified capsular polysaccharide markedly reduced the phagocytosis of P . haemolytica A1 in vitro in a dose-dependent manner . Both the percentage of macrophages with intracellular P . haemolytica and the mean number of bacteria per ingesting macrophage were decreased by treatment with capsular polysaccharide . Untreated bovine alveolar macrophages had little ability to kill P . haemolytica A1 in vitro at bacteria to macrophages ratios of 1 to 1 or greater; at lower ratios of bacteria to macrophages (1 to 3 or less) modest killing was observed . Preincubation with capsular polysaccharide impaired phagocytosis and killing of P . haemolytica A1 by alveolar macrophages even when the macrophages outnumbered the bacteria . These data indicate that P . haemolytica capsular polysaccharide inhibits the ability of alveolar macrophages to defend against P . haemolytica, as has been reported previously for bovine neutrophils.

Vet Microbiol, 1991 Feb 15, 26(4), 335 - 47
Opsonic monoclonal antibodies against lipopolysaccharide (LPS) antigens of Pasteurella multocida and the role of LPS in immunity; Ramdani et al.; A panel of six monoclonal antibodies (MAbs) produced from mice immunized with Pasteurella multocida (M1404) (Heddleston serotype 2) reacted with homologous lipopolysaccharide, as indicated by enzyme immunoassay and immunoblotting . All six MAbs reacted with serotypes 2 and 5 of the 16 Heddleston serotypes . The reactive epitopes were localized on the bacterial cell surface by immunogold labelling . The antibodies could agglutinate P . multocida only if cells were first treated with 1 N HCl . All six MAbs opsonized P . multocida for phagocytosis by mouse macrophages but were not bactericidal in the presence of complement . They afforded only partial protection against infection in mice . The results, together with those of active immunization experiments with LPS, suggest a subordinate role for LPS in protection from experimental infection in mice.

Vaccine, 1991 Feb, 9(2), 137 - 40
Vaccine containing iron-regulated proteins of Pasteurella haemolytica A2 enhances protection against experimental pasteurellosis in lambs; Gilmour NJ et al.; A vaccine containing sodium salicylate extract (SSE) of Pasteurella haemolytica A2 cells grown in a medium chemically depleted of available iron by the addition of alpha alpha dipyridyl to induce iron-regulated proteins (IRPs) conferred protection to specific pathogen-free (SPF) lambs exposed to an aerosol of P . haemolytica A2 . The disease score in these lambs was significantly lower (p less than 0.005) than those in unvaccinated lambs or in lambs immunized with SSE prepared from cells grown in iron-replete medium . Immunoblotting of sera from these SPF lambs against whole cell antigens of P . haemolytica A2 grown under iron-restricted conditions demonstrated that antibodies to IRPs were present only in the sera of animals immunized with SSE-IRP . The antibody profile of sera from the SSE-IRP group was similar to that obtained with serum from a lamb which had recovered from P . haemolytica A2 disease produced experimentally . Negligible levels of cytotoxin-neutralizing and bactericidal antibodies were detectable in the SSE-IRP group and therefore appear not to be involved in the protection observed in this experiment.

Vet Immunol Immunopathol, 1991 Feb, 27(4), 337 - 50
Interaction of bovine neutrophils in Pasteurella haemolytica mediated damage to pulmonary endothelial cells; Breider MA et al.; The purpose of these studies was to determine mechanisms of pulmonary tissue damage mediated by Pasteurella haemolytica and interaction with bovine neutrophils . Bovine pulmonary artery endothelial cell monolayers were treated with various combinations of P . haemolytica factors including bacterial culture supernatant (CS) and purified LPS, with and without bovine neutrophils . Damage to endothelial cells was monitored by 51Cr release, cell detachment rate, and morphological changes . At 5 h post-treatment (PT) bacterial factors produced very little toxic change in cells, however, by 22 h PT both crude leukotoxin and LPS caused high levels of cytotoxicity and detachment . Neutrophils did not augment toxicity mediated by LPS, but actually protected endothelial cells from low levels of LPS . When the LPS component of CS was neutralized with polymyxin B, leukotoxin mediated neutrophil killing resulted in extensive endothelial cell damage . These results suggest that LPS may directly injure endothelial cells and this toxic effect may be reduced by neutrophils . However, neutrophil killing by leukotoxin may also contribute to endothelial cell damage in the absence of LPS.

Vet Microbiol, 1991 Feb 1, 26(3), 213 - 25
A survey of potential virulence markers from avian strains of Pasteurella multocida; Lee MD et al.; Twenty-four isolates of Pasteurella multocida from clinical cases of fowl cholera and the Clemson University vaccine strain were surveyed for the presence of potential virulence markers . Membrane proteins, enzymatic activity of the membrane proteins, and carbohydrate fermentation patterns were also determined to demonstrate phenotypic relationships within the groups . Few differences were found in these phenotypic characteristics among the isolates . Almost all the organisms produced siderophore and were hemolytic on turkey red blood cells . No extracellular enzyme or bacteriocin activity was detected and little antibiotic resistance was found . However, many organisms contained plasmids and demonstrated some degree of resistance to complement . Both characteristics were correlative markers in Pasteurella multocida isolated from birds with fowl cholera.

Am J Vet Res, 1991 Feb, 52(2), 337 - 44
Changes in blood and bronchoalveolar lavage fluid components in calves with experimentally induced pneumonic pasteurellosis; Weiss DJ et al.; Pneumonic pasteurellosis was experimentally induced in calves by inoculation of 5 x 10(8) Pasteurella haemolytica organisms into the right diaphragmatic lung lobe . Blood and bronchoalveolar lavage fluid samples were obtained prior to inoculation and at postinoculation hour (PIH) 2, 4, and 6 . Calves developed acute lung injury, characteristic of pneumonic pasteurellosis . Lesions were found only in the right diaphragmatic lobe . By PIH 4, significant (P less than 0.01) increases were detected in lavage fluid total cell count, neutrophil count, total protein and albumin concentrations, and alkaline phosphatase (ALP) and lactic dehydrogenase (LD) activities . Myeloperoxidase and elastase activities did not increase . Neutrophil depletion ameliorated the lung lesions and prevented the increase in lavage fluid cell count, total protein, and albumin concentrations and ALP and LD activities . Treatment with the iron chelator, deferoxamine mesylatehydroxyethyl starch, attenuated the increase in total protein and albumin concentrations and ALP and LD activities at PID 4, but not PIH 6 . Treatment with a neutrophil function inhibitor, pentoxifylline, prevented the increase in lavage fluid neutrophil numbers, but accentuated the increase in total protein and albumin concentrations, and ALP, LD, myeloperoxidase, and elastase activities.

Am J Vet Res, 1991 Feb, 52(2), 212 - 6
Case control study of fowl cholera in meat turkeys in California from August 1985 through July 1986 {corrected}; Hird DW et al.; From Aug 1985 through July 1986, 720 meat turkey flocks on 160 California premises were monitored and outbreaks of fowl cholera (Pasteurella multocida) were investigated . Data from 43 outbreak (case) flocks were compared with data from 43 nonoutbreak (control) flocks . Outbreak flocks, compared with control flocks, were more likely to be located on premises with higher maximal bird capacity and history of fowl cholera outbreaks . The overall impression was that flocks in larger, newer, more intensively managed premises were at greater risk of fowl cholera outbreaks than were other flocks.

Infect Immun, 1991 Feb, 59(2), 587 - 91
Efficacy of recombinant leukotoxin in protection against pneumonic challenge with live Pasteurella haemolytica A1; Conlon JA et al.; The recombinant leukotoxin (rLKT) of the bacterium Pasteurella haemolytica A1 was examined for its ability to protect cattle from experimental challenge with logarithmic-phase P . haemolytica . Six different vaccines were utilized in the experiment: P . haemolytica culture supernatant, P . haemolytica culture supernatant enriched with rLKT, rLKT alone, P . haemolytica culture supernatant enriched with Escherichia coli supernatant not containing LKT, E . coli supernatant alone, and phosphate-buffered saline . rLKT alone showed no protective capacity against development of clinical signs of respiratory disease or against development of postmortem lung lesions after experimental challenge . It was, however, shown to enhance the efficacy of the culture supernatant vaccine and decrease clinical signs and pneumonic lesions . The complexity of protective immunity in this disease is emphasized in this study, and, although LKT is an important virulence factor of the organism, an immune response to LKT alone does not protect animals against disease.

J Gen Microbiol, 1991 Feb, 137 ( Pt 2), 219 - 26
Identification and localization of an iron-regulated 35 kDa protein of Pasteurella haemolytica serotype A2; Lainson FA et al.; Iodination of intact Pasteurella haemolytica serotype A2 cells labelled a sub-set of total cellular proteins . Comparison of the autoradiographic patterns obtained from iodinated cells grown on complete medium and on iron-depleted medium showed that expression of three proteins, of 100, 70 and 35 kDa, respectively, was increased by growth under iron-depleted conditions . Of these proteins, that of 35 kDa had not been reported previously . Like the 100 and 70 kDa proteins, the 35 kDa protein was expressed in natural infections, since it was recognized by antiserum from sheep that had recovered from an experimental infection with P . haemolytica A2 . The 35 kDa protein was partially purified by reverse-phase HPLC and was found to be antigenic in both sheep and mice . A monoclonal antibody that was specific for the 35 kDa protein was used to identify the cellular location of the protein by immunoblotting of cell fractions enriched for particular cellular components . This demonstrated that the 35 kDa protein was located mainly in the periplasm.

Ned Tijdschr Geneeskd, 1991 Jan 26, 135(4), 138 - 40
{Pasteurella multocida infections: bites by dogs or cats?}; Tjong Joe Wai R et al.; Annually 50,000 to 100,000 animal bites are seen by physicians in the Netherlands . Infections of these bite wounds frequently occur . Pasteurella multocida is one of the main causes of these infections and many serious complications may occur . We present 3 patients with disturbances in wound healing after animal bites or scratches due to infection with P . multocida . In view of the high infection ratio after cat bites we advise giving amoxicillin/clavulanic acid (Augmentin) for 5 days as prophylaxis . According to the literature prophylaxis for dog bites is not necessary . However, fatal complications after dog bites due to infections with Capnocytophaga canimorsus (DF-2) support those who prefer to give antibiotics after these bites also.

Am J Nephrol, 1991, 11(1), 61 - 3
Pasteurella multocida peritonitis in an HIV-positive patient on continuous cycling peritoneal dialysis; Elsey RM et al.; Pasteurella multocida has been reported only once previously as a cause of peritonitis in a patient undergoing chronic peritoneal dialysis . The present report describes findings associated with a case of P . multocida peritonitis in a human immunodeficiency virus (HIV)-positive patient in which renal replacement therapy consisted of continuous cycling peritoneal dialysis . To our knowledge this is the first report of this unique infection in an HIV-positive end-stage renal disease patient . In addition, the recent literature on this unusual organism is reviewed in detail . These findings emphasize the potential for increased susceptibility to zoonoses in immunocompromised patients, particularly with indwelling intraperitoneal catheters which may serve as a portal of entry for unusual organisms.

Avian Dis, 1991 Jan-Mar, 35(1), 93 - 9
Effects of adjuvant-augmented germling vaccines in turkey poults challenged with Aspergillus fumigatus; Richard JL et al.; Turkey poults were vaccinated with combinations of two different germling preparations and three adjuvants (N-acetylmuranyl-L-alanyl-D-isoglutamine, Pasteurella multocida lipopolysaccharide {LPS}, and avridine) at 1 and 2 weeks of age, and their immunity was challenged by sublethal exposure to aerosols of Aspergillus fumigatus conidia at 1 month of age . Fewer turkeys in the groups given vaccines prepared from germlings grown on Dorset's and Henley's medium (D&H) had organisms in lung tissue at 2 weeks after challenge exposure as compared with those vaccinated with germling grown on neopeptone dialysate (Neo) . The LPS of P . multocida appeared to be the most efficacious of the adjuvants in the D&H vaccine group, as A . fumigatus was isolated from only one of eight turkeys in this group; the number of organisms per gram of lung tissue was low compared with other vaccine groups at 2 weeks after challenge exposure; and poults given D&H vaccine with LPS as adjuvant had less-severe lung lesions than other groups . These differences in lung lesions were more marked at 2 weeks than at 8 weeks after challenge exposure . The only difference among other parameters in the vaccinated turkeys was lower heterophil counts in the turkeys given D&H-prepared vaccines than in unvaccinated controls . This was probably due to less-severe infections resulting from protective effects of these vaccines.

Avian Dis, 1991 Jan-Mar, 35(1), 126 - 34
Vaccination of turkeys with cell-free culture filtrate of Pasteurella multocida; Ficken MD et al.; Turkeys given cell-free culture filtrate (CCF) of Pasteurella multocida strain R44/6 orally, via air sacs, or subcutaneously mixed 1:1 with incomplete Freund's adjuvant (IFA) at 6 and 9.5 weeks of age were compared with negative controls given bacteriologic medium and positive controls vaccinated with a commercial bacterin . At 13 weeks of age, serum antibody titers to P . multocida were detectable only in turkeys given CCF in IFA (low titers) and positive control turkeys (high titers), at which time turkeys were challenged orally with either the homologous strain or strain P-1059 . Protection against challenge with strain R44/6 was provided by the commercial bacterin, CCF in IFA, and CCF given via air sacs . When turkeys were challenged with strain P-1059, protection was superior in turkeys given CCF via air sacs, intermediate in turkeys given commercial bacterin or CCF in IFA, and absent in negative control turkeys and turkeys given CCF orally . These results indicate CCF is an effective immunogen when administered via the lower respiratory tract for protecting turkeys against pasteurellosis.

Vet Microbiol, 1991 Jan, 26(1-2), 115 - 24
Reclassification of German, British and Dutch isolates of so-called Pasteurella multocida obtained from pneumonic calf lungs; Bisgaard M et al.; The taxonomic relationship of 131 strains previously identified as Pasteurella multocida obtained from calf pneumonia in West Germany, United Kingdom and Netherlands was investigated by extended phenotypic and limited genotypic characterization . Twenty-four strains were classified as P . multocida ssp . multocida, 15 strains as P . avium biovar 2 and 13 strains as P . canis biovar 2 . Sixty-five and five strains were tentatively classified as ornithine negative P . multocida ssp . multocida and P . multocida ssp . septica, respectively . Genetic investigations showed that ornithine negative strains of P . multocida were related on species level . Less genomic binding was found between an ornithine negative strain of P . multocida ssp . septica and the type strains of the three subspecies of P . multocida . The taxonomic position of ornithine negative strains of P . multocida is still under investigation . The taxonomic position of the remaining nine strains is uncertain underlining the need for genotypic characterization within the genus Pasteurella to aid in defining single species by phenotypic tests.

Vet Microbiol, 1991 Jan, 26(1-2), 107 - 14
Resistance to trimethoprim and 2,4-diamino-6,7-diisopropyl-pteridine (0/129) in Pasteurella haemolytica; Escande F et al.; Thirteen strains of Pasteurella haemolytica resistant to moderate levels of trimethoprim (MICs from 8 to 64 micrograms/ml) and 0/129 (MICs from 16 to 64 micrograms/ml) were isolated from bovine specimens . Two strains, CNP330 and CNP334, were studied and found to harbour various plasmids but all attempts to cure trimethoprim resistance were unsuccessful . Resistance characters were not transferable to Escherichia coli or to Pasteurella multocida by conjugation and to E . coli by transformation . The resistance gene(s) was therefore tentatively assigned to a chromosomal location and cloned into E . coli where it conferred trimethoprim resistance . Trans-complementation analysis of a dihydrofolate reductase-deficient mutant of E . coli showed that trimethoprim resistance was secondary to synthesis of a dihydrofolate reductase . DNA/DNA hybridization of the hybrid plasmid and of strains CNP330 and CNP334 with probes specific for dihydrofolate reductase types I to V were negative, indicating that cross-resistance to trimethoprim and 0/129 in P . haemolytica was due to the acquisition by P . haemolytica of a new resistance determinant.

J Wildl Dis, 1991 Jan, 27(1), 53 - 60
Detecting nonhemolytic Pasteurella haemolytica infections in healthy Rocky Mountain bighorn sheep (Ovis canadensis canadensis): influences of sample site and handling; Wild MA et al.; Effects of sampling procedures on ability to culture Pasteurella spp . from Rocky Mountain bighorn sheep (Ovis canadensis canadensis) were examined experimentally . Sample site influenced (P less than 0.0001) recovery of P . haemolytica in adult bighorn sheep . We isolated nonhemolytic P . haemolytica from 18 of 19 tonsillar swabs and 18 of 19 tonsillar biopsies from adult sheep, yet only four of 19 nasal swabs yielded isolates . Sample handling also affected (P less than 0.0001) recovery of P . haemolytica . Nonhemolytic P . haemolytica was cultured from 14 of 19 tonsillar swabs plated directly onto blood agar, but from only two of 19 swabs stored for 24 hr in modified Stuart's medium . We detected nonhemolytic P . haemolytica at least once in bronchial aspirates from four and in nasal swabs from three of six bighorn lambs . Based on direct cultures of tonsillar swabs and/or biopsies, all 26 bighorn sheep (seven lambs, 19 adults) sampled were infected with nonhemolytic P . haemolytica; only two lambs developed pneumonia during the study period . Thirty-four of 37 nonhemolytic P . haemolytica isolates tested were biotype T; three were biotype A . Serotypes 3; 4; 3, 4 and 3, 4, 10 were identified in a subsample of 17 isolates . Our data suggest tonsillar swabs or biopsies plated directly onto blood agar and incubated immediately offer the greatest probability of recovering nonhemolytic P . haemolytica from health bighorn sheep.

Am J Vet Res, 1991 Jan, 52(1), 34 - 9
Determination of affinity of Pasteurella multocida isolates for porcine respiratory tract mucus, and partial characterization of the receptors; Letellier A et al.; The ability of 25 Pasteurella multocida isolates to adhere in vitro to porcine respiratory tract mucus was examined . Microplate wells were coated with crude mucus preparation, then bacteria were added . After incubation, unbound bacteria were removed by washing, and the number of mucus-bound bacteria was estimated by quantitation of the adherent colony-forming units and by use of an ELISA . Pasteurella multocida had affinity to respiratory tract mucus, although significant differences were not observed in affinity of capsular type-A and type-D isolates . Preliminary characterization, using ultrafiltration, gel filtration chromatography, electrophoresis, and enzymatic treatments, indicated that the receptors may be a class of protein molecules of low molecular weight (less than 25,000) . The origin of these receptors, however, is not known at this time.

J Comp Pathol, 1991 Jan, 104(1), 23 - 32
Morphological and morphometrical analysis of the acute response of the bovine alveolar wall to Pasteurella haemolytica A1-derived endotoxin and leucotoxin; Whiteley LO et al.; Endotoxin or leucotoxin derived from Pasteurella haemolytica biotype A serotype 1 or saline was deposited by fibreoptic bronchoscopy into the caudal segment of the right anterior lung lobe of calves, and the lesions were characterized by light and transmission electron microscopy . Morphometric techniques were used to determine if changes in the arithmetic mean thickness of the alveolar wall occurred . Group 1 calves (n = 2) were inoculated with 6 ml saline, groups 2 calves (n = 3) received 6 ml of a partially purified leucotoxin preparation, group 3 calves (n = 3) received 96 micrograms of endotoxin in 6 ml of saline and group 4 calves (n = 3) received 2.5 mg of endotoxin in 6 ml of saline . Calves were killed 4 h after inoculation . Lesions in groups 2, 3 and 4 were similar and we found that (a) endotoxin alone is capable of initiating an inflammatory response in the bovine lung, (b) leucotoxin causes cytotoxic changes in alveolar macrophages but not in parenchymal cells of the lung, (c) neutrophil sequestration and platelet aggregation occur in alveolar capillaries in association with pulmonary intravascular macrophages, (d) neutrophils and fibrin were found in the alveolus in close association with alveolar macrophages, (e) disruption of the alveolar epithelial layer occurred in association with neutrophils and (f) there were no significant increases in the arithmetic mean thickness of the alveolar wall.

Vet Pathol, 1991 Jan, 28(1), 46 - 54
Acute airsacculitis in turkeys inoculated with cell-free culture filtrate of Pasteurella multocida; Ficken MD et al.; Twenty-six female and 26 male turkeys, inoculated into the caudal thoracic air sacs with cell-free culture filtrate of Pasteurella multocida strain R44/6, were examined from 0 to 6 hours post-inoculation and compared with 26 female and 26 male sham-inoculated control turkeys given brain-heart-infusion broth . The air sac reacted rapidly with exudation of heterophils . Microscopically, low numbers of heterophils were present within air sac blood vessels and also perivascularly by 0.5 hour after inoculation . These became more numerous by 1.5 and 3 hours post-inoculation . By 6 hours post-inoculation, there was severe swelling of air sac epithelial and mesothelial cells and thickening of the air sac by proteinaceous fluid and heterophils . Ultrastructurally, mesothelial and air sac epithelial cells were vacuolated, and interdigitating processes of epithelial cells were separated . Microscopically, in control turkeys, rare heterophils were present perivascularly at 1.5, 3, and 6 hours after inoculation . Ultrastructurally, all features were normal . In turkeys given cell-free culture filtrate, total cell counts in air sac lavage fluids increased markedly by 3 hours post-inoculation in which heterophils predominated (greater than 97%) . There were only slight increases in cell counts of air sac lavages from control turkeys . The circulating blood heterophil cell count dropped transiently at 1.5 hours post-inoculation, followed by a return to normal 3 hours after inoculation, and by heterophilia by 6 hours post-inoculation in turkeys given either cell-free culture filtrate or brain-heart-infusion broth . These results indicate cell-free culture filtrate of P . multocida induces hematologic, cytologic, and morphologic changes indistinguishable from those induced by cultures of P . multocida.

Infect Immun, 1991 Jan, 59(1), 172 - 80
A monoclonal antibody against a Pasteurella multocida outer membrane protein protects rabbits and mice against pasteurellosis; Lu YS et al.; Monoclonal antibodies (MAbs) directed against the 37.5-kDa outer membrane protein were produced by fusing myeloma cells with spleen cells obtained from mice immunized with a pathogenic strain of Pasteurella multocida isolated from a rabbit . Desirable MAbs were selected by enzyme-linked immunosorbent assay, whole-cell radioimmunoprecipitation (WC-RIP), and Western blot (immunoblot) analysis . WC-RIP and Western blot analyses, using MAb 1608 adsorbed with intact P . multocida cells and the eluted MAb, demonstrated that the antigen recognized by this MAb is exposed on the cell surface, is antibody accessible, and has an estimated molecular mass of 37.5 kDa . Treatment of outer membrane vesicles of P . multocida with proteinase K totally abrogated the MAb 1608 activity, indicating that this MAb binds to a protein antigenic determinant . Furthermore, MAb 1608 was nonreactive to purified lipopolysaccharide in Western blot analysis . Passive transfer studies showed that nine rabbits inoculated intranasally with MAb 1608 and homologously challenged intranasally had significantly reduced mortality, severity of pneumonia, prevalence of P . multocida colonization in nonrespiratory organs, and numbers of P . multocida in nasal cavities compared with the controls . Furthermore, the number of P . multocida in lungs was reduced 84,750-fold . Similarly, passive transfer experiments indicated that MAb 1608 protected mice against homologous and heterologous challenges with P . multocida strains bearing the antigenic determinant recognized by MAb 1608 . However, no protection was afforded by MAb 1608 when mice were challenged with a P . multocida strain lacking the antigenic determinant recognized by MAb 1608 . This study establishes that the 37.5-kDa outer membrane protein is the target for a protective MAb.

Acta Vet Scand, 1991, 32(1), 67 - 77
An abattoir survey of pneumonia and pleuritis in slaughter weight swine from 9 selected herds . II . Enzootic pneumonia of pigs: microbiological findings and their relationship to pathomorphology; Falk K et al.; Lungs from 191 slaughter pigs with gross lesions indicative of enzootic pneumonia of pigs (EPP) and 80 grossly normal lungs, all originating from 9 different herds, were subjected to microbiological and pathological examinations . The microbiological studies included both bacterial and mycoplasmal culture and also testing for Mycoplasma hyopneumoniae antigen in tissue by indirect immunofluorescent technique . M . hyopneumoniae, Pasteurella multocida and Mycoplasma hyorhinis were detected in 83%, 43% and 37% of the pneumonic lungs, respectively . Mycoplasma flocculare was the most frequently isolated organism in the non-pneumonic lungs . The greatest amounts of macroscopic pneumonia (25.2%) were recorded in lungs with all the three agents M . hyopneumoniae, P . multocida and M . hyorhinis present . The amounts of pneumonia in lungs with M . hyopneumoniae alone and in concurrence with P . multocida, were 9.3% and 15.6%, respectively . M . hyorhinis was also, in this study, associated with higher frequency of diffuse pleuritis . These findings indicate that M . hyorhinis might be involved in the pathogenesis of pneumonia in slaughter pigs . Ninety-six per cent of the isolates of P . multocida from pneumonic lungs could be characterized as type A . In the herds which had the most severe pneumonia problems, toxin production was detected in 83% of the P . multocida strains while only 28% were toxigenic in herds with subclinical to moderate pneumonia problems.

Ann Rech Vet, 1991, 22(2), 211 - 8
Adherence of Pasteurella multocida isolated from pigs and relationship with capsular type and dermonecrotic toxin production; Vena MM et al.; Pasteurella multocida can often be isolated from pneumonic lungs in pigs . There is little information about the pathogenesis of this infection . Attachment of microorganisms to eucaryotic cells is considered to be a prerequisite for colonization of the host in the pathogenesis of bacterial infections . Forty-seven P multocida strains isolated from pigs in France, and belonging to capsular type A or D were tested for their ability to agglutinate human erythrocytes, and to adhere to tracheal and lung cells . Each isolate was tested for dermonecrotic toxin production . Adherent strains were further observed by electron microscopy to look for attachment structure . Only type A strains agglutinated human O erythrocytes, but no relationship was observed between hemagglutination and dermonecrotic toxin production . The results of the adherence tests showed a greater affinity (P less than 0.05) of type A strains for lung cells (50% were adherent, whereas only 20% of type D strains were adherent) but did not reveal any correlation between adherence and the presence of dermonecrotic toxin . Microscope observations showed that these P multocida strains did not possess any pili-like structures . In conclusion, by means of the adherence test we were able to demonstrate a stronger adherence of type A strains and this adherence did not seem to be related to pili-like structures.

Vet Res Commun, 1991, 15(3), 189 - 204
The effects of stressful exercise on leukocytes in cattle with experimental pneumonic pasteurellosis; Anderson NV et al.; Seven yearling bulls were treated with stressful exercise and intrabronchial Pasteurella haemolytica A1 . Group 1 bulls (nos . 1-4) underwent treadmill exercise and, 24 days later, intrabronchial instillation of P . haemolytica A1 . Group 2 bulls (nos . 5-7) underwent treadmill exercise, followed 30 min later by intrabronchial P . haemolytica A1 . Blood lactic acid values were raised (p less than 0.05) by treadmill exercise only, but plasma cortisol was raised (p less than 0.05) by treadmill exercise and by P . haemolytica A1 infection . Neutrophils in bronchoalveolar lavage (BAL) differed from control values 24 h after treadmill exercise, and 1 h and 4 h after P . haemolytica A1 infection . Respiratory disease was more severe and the gross lung lesions were larger in group 2 bulls than in group 1 bulls . P . haemolytica A1 was recovered from the livers, spleens and mesenteric lymph nodes of group 2 but not group 1 bulls, suggesting that group 2 bulls had experienced bacteraemia . Decreased neutrophils in BAL fluid from group 2 bulls at 1 h and 4 h after infection suggests that exercise transiently inhibited neutrophil egress from the blood to the alveoli; BAL neutrophils peaked at 1 h and 4 h after infection in group 1 bulls but declined at 24 h . We conclude that group 2 bulls were made more susceptible to experimental pneumonic pasteurellosis by stressful exercise.

Med Microbiol Immunol (Berl), 1991, 180(2), 79 - 92
Carbohydrate patterns, cellular lipoquinones, fatty acids and phospholipids of the genus Pasteurella sensu stricto; Engelhard E et al.; The carbohydrate patterns, isoprenoid quinones, fatty acids and phospholipids of the species of the genus Pasteurella sensu stricto were investigated to evaluate their taxonomic significance and their applicability for the identification of these bacteria . Forty-six representative strains of the 11 species of Pasteurella were examined . The data obtained indicated that the carbohydrate patters are species or subspecies specific and may, therefore, become an important and useful diagnostic tool . Fatty acids and phospholipids showed a feature characteristic of the members of the genus and the isoprenoid quinones exhibited a mostly genus-specific feature with remarkable quantitative differences.

Lab Anim Sci, 1991 Jan, 41(1), 22 - 5
Chronic sialodacryoadenitis virus (SDAV) infection in athymic rats; Hajjar AM et al.; Sialodacryoadenitis virus (SDAV) was detected in athymic rats subcutaneously implanted with human tumor cell lines . Clinical signs included sneezing, dyspnea, weight loss and death . Necropsy revealed both upper and lower respiratory tract disease from which Staphylococcus aureus, Pasteurella pneumotropica and Pseudomonas aeruginosa were recovered . Histopathological changes consisted of suppurative rhinitis and bronchopneumonia . Lesions characteristic of SDAV infection were found in lacrimal and salivary glands, and viral antigens were detected in the salivary glands and respiratory tract by immunohistochemistry . Submaxillary salivary gland . Harderian gland and lung homogenates from affected athymic rats were inoculated intranasally into euthymic rats as a rat antibody production test . All euthymic rats seroconverted to SDAV . Seroconversion to SDAV was demonstrated in consecutive pairs of sentinel euthymic rats housed for 6 months with infected athymic rats . Inoculation of supernatants of the original tumor cell lines into euthymic rats did not result in seroconversion . The source of the virus was not determined . In this study, spontaneously acquired SDAV infection persisted for at least 6 months in athymic rats.

Acta Vet Hung, 1991, 39(3-4), 127 - 35
Prevention and treatment of atrophic rhinitis in pigs with Getroxel, chlorquinaldol and oxytetracycline; Varga J et al.; The sensitivity of ten Bordetella bronchiseptica and ten Pasteurella multocida strains, each isolated from cases of atrophic rhinitis (AR), was examined in tube dilution test . Getroxel, chlorquinaldol and oxytetracycline and the former two ones combined with trimethoprim inhibited the growth of both species in vitro . The minimum inhibitory and the minimum bactericidal concentration was less than 0.5 microgram/ml . When efficacy was tested in SPF in the group fed a combination of Getroxel, chlorquinaldol and oxytetracycline (60 mg, 240 mg and 360 mg/kg of feed, respectively), P . multocida disappeared from the nasal cavity by the end of a 30-day treatment . B . bronchiseptica was reisolated in low numbers from 2 out of 9 piglets . The daily body mass gain was by 7.9% higher and the feed conversion rate was by 19% better than in the control group . After slaughter, only mild signs of AR were seen in 3 out of 9 piglets treated with the above-mentioned drug combination, while in the control group severe lesions were observed in 8 out of 9 pigs . In treated commercial herds P . multocida disappeared from the nasal cavity of the piglets by the end of the treatment (42nd day of life), but the B . bronchiseptica strains could not be completely eliminated . Due to the treatment, mortality between 2 and 6 weeks of age decreased by 0.8-7.6% . Daily body mass gain was, on the average, 16.4% higher, the amount of feed needed for 1 kg body mass gain was by 15.3% lower and the duration of fattening was by 30.8 days shorter than in the control groups.

Am J Vet Res, 1991 Jan, 52(1), 56 - 61
Induction of pneumonia in rabbits by use of a purified protein toxin from Pasteurella multocida; Chrisp CE et al.; Heat-labile toxin from a cell sonicate of a virulent type-D strain of Pasteurella multocida was purified by ammonium sulfate precipitation followed by ion exchange chromatography, gel filtration chromatography, and polyacrylamide gel electrophoresis . Toxic activity was assayed during toxin purification by cytopathic effect in Vero or bovine embryonic lung cell cultures . Toxicity for cells correlated with dermonecrosis in guinea pig skin . Toxicity was accounted for by a single protein with a molecular weight of 149,000, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis . Rabbits were inoculated intranasally with purified toxin to determine whether toxin had a role in the induction of pneumonia in rabbits infected with P multocida . Pneumonia, pleuritis, acute hepatic necrosis, and splenic lymphoid atrophy were found in 4 of 5 rabbits . One of 5 rabbits had bilateral turbinate atrophy . Western blotting with monoclonal antibodies to toxin from a P multocida isolate causing atrophic rhinitis in pigs revealed the toxin that induces pleuritis and pneumonia in rabbits to be the same or a closely related toxin.

Acta Vet Hung, 1991, 39(1-2), 13 - 9
Abortion of a sow caused by Pasteurella aerogenes; Fodor L et al.; Three strains of the Pasteurella aerogenes complex were isolated as sole pathogens from aborted fetuses of a sow aborted at the 12th week of gestation on a farm of 600 sows . Gross pathology showed no characteristic lesions . The isolates were biochemically identical and resembled P . pneumotropica on the basis of their strong indole and urease positivity but they produced gas, were ornithine decarboxylase negative and fermented mannitol but not trehalose . Only a few differences were apparent in biochemical characteristics between the isolated strains and P . aerogenes . They differed from the type strain of P . aerogenes in ornithine decarboxylase activity, indole production and lactose and mannitol fermentation; however, such strains do occur within this heterogeneous species . At the time of abortion the antibody titre of the aborted sow was 1 in 16 when examined with live bacterial suspension and 1 in 128 if boiled antigen was used . Similar strains could not be isolated from the vaginas of aborted sows or pregnant and newly farrowed sows in the same group . The bacteriological, serological and histological findings support the opinion of other workers on the occasional pathogenic nature of P . aerogenes.

FEBS Lett, 1990 Dec 17, 277(1-2), 59 - 64
Sequence analysis of the potent mitogenic toxin of Pasteurella multocida; Lax AJ et al.; Pasteurella multocida toxin is a potent mitogen for cultured Swiss 3T3 cells where it causes an accumulation of inositol phosphates and activation of protein kinase C . The gene sequence described here coded for a 146 kDa protein . The ORF was preceded by a ribosome binding site and followed by a stem loop . There was no evidence for a signal sequence . The gene had a low G + C base ratio which differs from the rest of the Pasteurella genome . There was no significant homology with other known proteins, although a motif found in certain bacterial toxins which are ADP-ribosyl transferases is present . A recombinant expressing only part of the PMT gene was not mitogenic.

J Med Microbiol, 1990 Dec, 33(4), 217 - 22
Production of mouse monoclonal antibodies to Pasteurella multocida type A and the immunological properties of a protective anti-lipopolysaccharide antibody; Wijewardana TG et al.; Eight monoclonal antibodies (MAbs) were produced from mice immunised with whole cells of heat-killed Pasteurella multocida type A which had been cultured under iron-restricted conditions . The MAbs were selected by an enzyme-linked immunosorbent assay (ELISA) in which the antigen consisted of whole bacteria of the immunising strain . Their reactivity was investigated further by immunoblotting, indirect haemagglutination, a complement-mediated bactericidal assay and passive protection of mice . One of the eight MAbs was shown by immunoblotting to react with lipopolysaccharide (LPS), was bactericidal, and completely protected mice against homologous challenge with 10 LD50 of live bacteria . This MAb was selected for further study . Its reaction with LPS of 17 type-A strains and of single strains of types B, D and E was investigated by immunoblotting . Strains that reacted with the anti-LPS MAb in immunoblots were susceptible to its bactericidal activity and gave high ELISA absorbances . Those that did not react were not susceptible to its bactericidal activity and gave low ELISA readings . The relation between bactericidal activity and ELISA absorbance was highly significant (p less than 0.001) . Five of the strongly reacting heterologous strains and one non-reacting strain were selected as challenge organisms in a passive protection experiment: only the mice receiving the reacting strains were protected.

Ann Emerg Med, 1990 Dec, 19(12), 1458 - 61
Erythromycin failure with subsequent Pasteurella multocida meningitis and septic arthritis in a cat-bite victim; Levin JM et al.; We report the case of a 75-year-old woman who developed Pasteurella multocida meningitis and septic arthritis while being treated for a cat-bite wound infection with erythromycin . Review of the literature revealed that erythromycin has poor in vitro activity against this bacterium and has been associated with serious clinical failures . We recommend that erythromycin not be prescribed for empiric therapy of established animal-bite infections . Suggestions for optimal empiric therapy of animal-bite infections and the differential diagnosis of severe cat-bite-associated sepsis are discussed.

Dtsch Tierarztl Wochenschr, 1990 Dec, 97(12), 529 - 32
The efficacy of danofloxacin in the therapy of pneumonia associated with Pasteurella species in housed calves; Grimshaw WT et al.; The efficacy of danofloxacin, a novel third generation fluoroquinolone, was assessed in the treatment of pneumonia in housed calves on three farms in the FDR and Italy . Seventy three calves with clinical signs of acute pneumonia and rectal temperatures greater than 40 degrees C were treated with danofloxacin at a dose rate of 1.25 mg/kg for three or five days depending on response to treatment . The response in these calves was compared to that obtained in 77 calves treated with trimethoprim/sulpha . The clinical response achieved with danofloxacin was superior to that achieved with trimethoprim/sulpha and significantly fewer calves which received danofloxacin required five days treatment . Pasteurella haemolytica and, or P . multocida were isolated from the majority of calves prior to treatment . All isolates were sensitive to danofloxacin and over 90 percent were sensitive to trimethoprim/sulpha.

J Med Assoc Thai, 1990 Dec, 73(12), 704 - 6
Pasteurella multocida infective endocarditis: a case report; Thamlikitkul V et al.; A 17-year-old man presented with acute febrile illness with jaundice, embolic skin lesion, heart murmur, renal insufficiency and abnormal CSF . Pasteurella multocida was isolated from blood cultures . In spite of adequate antibiotic treatment for endocarditis of the mitral valve, he developed a fatal ruptured cerebral mycotic aneurysm . Post mortem examination revealed an atrial septal defect, vegetation at the anterior mitral leaflet, intraventricular, subarachnoid and intracerebral hemorrhage.

Poult Sci, 1990 Dec, 69(12), 2134 - 42
Immunity to Pasteurella multocida in protein-deficient chickens; Payne CJ et al.; Studies were conducted to determine the effects of dietary protein restriction on the humoral immunity (HI) and cell-mediated immunity (CMI) of chickens . New Hampshire chickens were separated into two dietary treatment groups: basal, containing 3,200 kcal/kg and 21% protein; or protein restricted (PR), containing 3,200 kcal/kg and 7% protein . In studies involving HI, half of the birds in each dietary treatment were vaccinated against fowl cholera at 4 and 8 wk of age . Blood samples were collected weekly beginning at 4 wk of age . Overall, unvaccinated birds had lower titers than vaccinated birds and PR groups generally showed lower titers than basal groups . All birds were challenged by palatine cleft inoculation of live, virulent Strain X-73 of Pasteurella multocida . The vaccinated PR group survived live challenge as well as the vaccinated basal group, but all unvaccinated birds died as a result of the challenge, regardless of antibody titer . In studies involving CMI, half of the birds in each dietary treatment were vaccinated at 5 wk of age . At 2 to 3 wk postvaccination, representative birds from each treatment were bled for total and differential blood counts . Also, birds were sacrificed and spleen cells collected . Cells were cultured in Roswell Park Memorial Institute (RPMI) medium with phytohemagglutinin-M (PHA-M), sonicated P . multocida (X-73), or RPMI only.(ABSTRACT TRUNCATED AT 250 WORDS)

FEMS Microbiol Immunol, 1990 Dec, 2(5-6), 269 - 78
The susceptibility of in vivo-grown Pasteurella haemolytica to ovine defence mechanisms in vitro; Sutherland AD et al.; Pasteurella haemolytica organisms grown in vivo were examined for their susceptibility to ovine immune mechanisms in vitro . Compared with in vitro grown organisms they were less susceptible to opsonophagocytosis and, in contrast, susceptible to complement-dependent killing in the absence of exogenous antibody . These differences were not associated with phenotypic changes in the surface of the bacterial cell . However, overproduction and de novo synthesis of proteins was observed in in vivo grown organisms . Also, bound host-immunoglobulin was observed on in vivo grown organisms and a role for this in modifying the interaction with immune mechanisms is discussed.

Vet Microbiol, 1990 Nov, 25(2-3), 241 - 51
Resistance to host immune defense mechanisms afforded by capsular material of Pasteurella haemolytica, serotype 1; Chae CH et al.; Selected serum-mediated host immune defense mechanisms against Pasteurella haemolytica were studied using encapsulated and decapsulated organisms . When the capsular material was removed from P . haemolytica, it became more susceptible to serum agglutination, complement-mediated serum killing, and phagocytosis by polymorphonuclear leukocytes . When encapsulated organisms were used, phagocytosis was enhanced by antibodies to capsular material produced by vaccination of calves with any of three P . haemolytica vaccines . The serum bactericidal activity, however, was not facilitated by increased levels of anticapsular antibody in vaccinated cattle . By contrast, when decapsulated organisms were used, vaccination enhanced both the bactericidal and opsonizing capacities of sera from the calves . These studies indicate that capsular material should be considered a principal virulence factor for P . haemolytica.

Anat Rec, 1990 Nov, 228(3), 237 - 46
Effects of purified Pasteurella multocida dermonecrotoxin on cartilage and bone of the nasal ventral conchae of the piglet; Martineau-Doize B et al.; The effect of intramuscular injection of purified dermonecrotoxin (DNT) from Pasteurella multocida type D on the nasal ventral conchae of piglets was studied . Severe atrophy of the conchae was observed 4, 6, and 10 days after injection (p.i.d) . Lesions were observed in conchae cartilage and bone . Cartilage changes observed were the absence of chondrocyte maturation and hypertrophy, hyaline cartilage invasion by fibroblast-like and multinucleated cells, and endothelium damage with haemorrhages along the cartilage . Intramembranous bone was absent on p.i.d . 4, 6, and 10 . Lamellar bone trabeculae were rarefied on p.i.d . 4 and almost absent on p.i.d . 10 . Trabeculae were either normal or had the aspect of a dissolved bone matrix, leaving only irregularly oriented collagen fiber bundles . The number of osteoclasts was increased, especially the subperiosteal osteoclasts at the eccentric side of the scrolls . The osteoblasts appeared normal or their cytoplasm was dilated by vacuoles . It is concluded that the macroscopic conchae atrophy results from histological alterations and subsequent loss of both cartilage and bone . Further investigation is necessary to know whether the toxic effect of DNT on cells and matrix is direct or dependent of the vascular damage.

Am J Vet Res, 1990 Nov, 51(11), 1860 - 4
In vitro susceptibility of some porcine respiratory tract pathogens to aditoprim, trimethoprim, sulfadimethoxine, sulfamethoxazole, and combinations of these agents; Mengelers MJ et al.; The in vitro antimicrobial activities of aditoprim (AP), a new dihydrofolate reductase (DHFR) inhibitor, trimethoprim (TMP), sulfadimethoxine (SDM), sulfamethoxazole (SMX), and combinations of these drugs against some porcine respiratory tract pathogens were determined by use of an agar dilution method . The minimal inhibitory concentrations (MIC) of these agents were determined twice against Bordetella bronchiseptica (n = 10), Pasteurella multocida (n = 10), and Actinobacillus pleuropneumoniae (n = 20) strains isolated from pigs suffering from atrophic rhinitis or pleuropneumonia . All B bronchiseptica strains were resistant to AP and TMP . The MIC50 values of AP and TMP for P multocida were 0.25 and 0.06 microgram/ml, respectively, and for A pleuropneumoniae, 1 and 0.25 microgram/ml, respectively . The MIC50 values of SDM and SMX for B bronchiseptica were 4 and 1 micrograms/ml, respectively; for P multocida, 16 and 8 micrograms/ml, respectively; and for A pleuropneumoniae, 16 and 8 micrograms/ml, respectively . The investigated combinations of the DHFR inhibitors and the selected sulfonamides had synergism for the A pleuropneumoniae strains; the MIC90 values of the combinations were less than or equal to 0.06 microgram/ml . Potentiation was not observed for the B bronchiseptica and the P multocida isolates . The MIC of the combinations against B bronchiseptica and P multocida corresponded respectively to the concentrations of the sulfonamides and the DHFR inhibitors in the combinations . For A pleuropneumoniae, 2 types of strains were used (25% of serotype 2 and 75% of serotype 9) . Type-2 strains had lower susceptibility than type-9 strains to AP and TMP as well as to SDM and SMX (at least a fourfold difference in MIC between the 2 types of strains).(ABSTRACT TRUNCATED AT 250 WORDS)

Am J Vet Res, 1990 Nov, 51(11), 1799 - 805
Pneumonic pasteurellosis induced experimentally in gnotobiotic and conventional calves inoculated with Pasteurella haemolytica; Vestweber JG et al.; Experimental pneumonia caused by Pasteurella haemolytica was induced in 2-week-old gnotobiotic (n = 4) and conventional (n = 6) calves by endobronchial inoculation into the right caudal lung lobe of 7.9 x 10(10) +/- 0.6 x 10(10) (mean +/- SD) colony-forming units of P haemolytica in the 6-hour log phase of growth . The calves were studied for 24 hours or less . Regression lines for the relationship between clinical index and time for the gnotobiotic group and conventional group of calves were compared, and the clinical index was found to be significantly (P less than or equal to 0.005) more rapid in the gnotobiotic group . There was also a significant difference in the preinoculation, absolute segmented neutrophil count (P less than or equal to 0.05), and in the total serum protein, albumin, and globulin values (P less than or equal to 0.05) . Comparison of the preinoculation and post inoculation blood cell and blood chemical values revealed a significant increase (P less than or equal to 0.05) in the numbers of band neutrophils and fibrinogen in conventional calves, and a significant decrease (P less than or equal to 0.05) in the total WBC count in gnotobiotic calves . Necropsy of both groups of calves revealed a circular to oblong lesion that was congested, edematous, and firm, and which occupied 20% to 100% of the right caudal lung lobe and involved the remaining lung lobes to a more minor degree . When mean lesion scores of the 2 groups of calves were compared, no significant difference (P less than or equal to 0.05) was found.(ABSTRACT TRUNCATED AT 250 WORDS)

Am J Vet Res, 1990 Nov, 51(11), 1792 - 8
Clinical and pathologic studies of experimentally induced Pasteurella haemolytica pneumonia in calves; Vestweber JG et al.; Pasteurella haemolytica pneumonia of the right caudal lung lobe was experimentally induced in 2-week-old Holstein calves (n = 11) by endobronchial inoculation of 7.9 x 10(10) colony-forming units of 6-hour log-phase bacteria . Calves were studied for 72 hours after inoculation . The challenge procedure consistently induced a lesion in the right caudal lung lobe, which was consistent radiographically with results of pathologic examination and a similar volume of bronchography contrast medium . Clinically, the calves developed a significant increase in rectal temperature within 24 hours after inoculation . Seventy-two hours after inoculation, the total WBC counts, absolute band neutrophil counts, monocyte counts, and blood fibrinogen concentrations were significantly higher than normal and albumin concentration was significantly decreased . Necropsy revealed a circular to oblong lesion that was congested, edematous, and firm and occupied 20 to 40% of the right caudal lung lobe . Histologic examination revealed a severe acute inflammatory reaction characterized by cellular exudate and proteinaceous fluid in the alveoli, interlobular septa, and pleura.

Vet Microbiol, 1990 Nov, 25(2-3), 253 - 65
Colonisation by Pasteurella multocida in atrophic rhinitis of pigs and immunity to the osteolytic toxin; Chanter N et al.; Gnotobiotic pig antisera to purified toxoid from a capsule type A or D strain of Pasteurella multocida contained large quantities of antitoxin but comparatively little antibody to a crude lysate of P . multocida . These sera given intraperitoneally to further pigs were almost completely protective against turbinate atrophy after intranasal inoculation of dilute acetic acid and infection with type D toxigenic P . multocida . In contrast, antisera to a crude lysate or bacterin of toxigenic P . multocida which contained large titres of antibody to P . multocida lysate, but no detectable antitoxin, were not protective . Colonisation by toxigenic P . multocida was significantly reduced in protected pigs and was similar to colonisation by nontoxigenic P . multocida in pigs untreated or treated with dilute acetic acid . These results indicated (1) that antitoxin was protective and cross protective between toxins from different capsule types; and (2) that the toxin was the main colonisation factor produced by toxigenic bacteria in the acetic acid model of infection and that immunity to it did not eliminate infection.

Res Vet Sci, 1990 Nov, 49(3), 261 - 7
Rapid identification of Pasteurella multocida organisms responsible for haemorrhagic septicaemia using an enzyme-linked immunosorbent assay; Dawkins HJ et al.; Haemorrhagic septicaemia (HS) is caused by specific serotypes of Pasteurella multocida and is one of the major economic diseases of cattle and buffalo in South East Asia . Definitive diagnosis of the disease-causing organism with the available methods is labour intensive and not totally reliable, consequently, an ELISA system to identify P multocida organisms which cause HS was developed . One hundred and twenty-four P multocida isolates were tested, 58 were type strains and 66 were field isolates . Analysis of these strains indicated the assay had a specificity of 99 per cent and sensitivity of at least 86 per cent . The sensitivity could be an underestimate, as five isolates assumed to be false negative reactions may not all be HS-causing strains . The HS ELISA provides a rapid, simple, accurate and inexpensive diagnostic assay for identification of HS causing organisms but does not represent a new typing system for P multocida . This assay will also enable countries to assess the impact of HS more accurately.

Mol Microbiol, 1990 Nov, 4(11), 1933 - 9
Deletion analysis resolves cell-binding and lytic domains of the Pasteurella leukotoxin; Cruz WT et al.; A series of internal deletions in the lktA gene of Pasteurella haemolytica has been constructed . All of the deletions eliminated the lytic activity of the leukotoxin towards the bovine lymphoma cell line, BL-3 . Deletions removing segments of the amino-proximal hydrophobic region, which is thought to constitute an essential membrane-spanning domain, were found to agglutinate BL-3 cells . Agglutination was similar to lysis by the wild-type toxin in that it was dependent upon the presence of calcium and required expression of the lktC gene . The agglutinating deletion proteins protected BL-3 cells from lysis by the wild-type toxin in a competitive fashion . This suggests that these mutants bind to a surface feature of the leukocyte which interacts with the native leukotoxin . These findings demonstrate that the cell-binding and lytic domains of the leukotoxin are separable.

J Gen Microbiol, 1990 Nov, 136 ( Pt 11), 2173 - 8
Time and temperature dependence of granulocyte damage by leucotoxic supernatants from Pasteurella haemolytica A1; Styrt B et al.; Bacterial exotoxins may contribute to the pathogenic potential of micro-organisms through interactions with cells of the host defence system as well as by directly damaging host tissue . The present studies were designed to explore mechanisms of interaction between bovine granulocytes and the leucotoxin produced by Pasteurella haemolytica, a major cause of bovine respiratory disease . Leucotoxin-containing supernatant from P . haemolytica A1 caused rapid cell death in isolated bovine granulocytes that was close to half-maximal by 5 min and nearly 90% complete after 30 min at 37 degrees C . Maintaining granulocytes at ice-water temperature markedly attenuated or prevented the toxic effect; furthermore, if exposed to supernatants at ice-water temperature and then washed, most cells remained viable even after rewarming to room temperature . However, even a very brief exposure (about 5 s) at 37 degrees C led to extensive cell death even after immediate cold dilution and washing . Granule enzymes such as arylsulphatase were released far more slowly than cytosol contents . Leucotoxin purified by column chromatography showed temperature dependence and divergence between cytosol and granule marker release similar to those observed with the crude supernatant preparation . These findings indicate that irreversible interaction between P . haemolytica leucotoxin and bovine granulocytes is initiated very rapidly at 37 degrees C but markedly impeded at low temperature, while granule enzyme release follows cytosol marker release over a much longer period . The results suggest either a requirement for target cell metabolic activity to initiate toxin effects or a temperature-dependent receptor conformation, with granule enzyme release following as a secondary consequence of granulocyte death.

J Comp Pathol, 1990 Nov, 103(4), 411 - 20
Increased susceptibility to Pasteurella haemolytica in lambs infected with bovine respiratory syncytial virus; Sharma R et al.; Groups of conventionally reared, 6- to 8-week-old lambs were inoculated intranasally and intratracheally with either bovine respiratory syncytial virus (BRSV) or BRSV followed by Pasteurella haemolytica 6 days later or with P . haemolytica alone . Lambs infected with P . haemolytica 6 days after experimental infection with BRSV had significantly higher disease scores, greater magnitudes of fever, and higher mortality rates than those infected with BRSV alone or with P . haemolytica alone (P less than 0.05) . Mononuclear cells in the peripheral blood and lung lavage obtained from the BRSV-infected lambs were more susceptible to P . haemolytica cytotoxin than those obtained from control lambs (P less than 0.05) . P . haemolytica was isolated in significantly greater numbers from lambs infected with BRSV and P . haemolytica than from those infected with P . haemolytica alone (P less than 0.05).

Berl Munch Tierarztl Wochenschr, 1990 Nov 1, 103(11), 365 - 71
{Pasteurella multocida (type D and A) and atrophic rhinitis of swine--hemagglutination, fimbriae and adhesion in vitro in the nasal mucosa of swine fetuses}; Grund S et al.; 79 strains of P . multocida were investigated, mostly isolated from porcine nasal cavities, and a mannose-resistant hemagglutination with guinea pig and human group 0, but not with porcine erythrocytes was found . Fimbriae as adhesins were demonstrated only on 2 strains . A correlation between capsular type, hemagglutination, fimbriation and toxigenicity on the examined P . multocida strains was not observed . Three strains were investigated for the adherence to the nasal mucosa of neonatal pigs; aggregates shown by scanning electron microscopy indicate colonization; a correlation of adherence with surface proteins and slime production of P . multocida is discussed.

Schweiz Rundsch Med Prax, 1990 Oct 16, 79(42), 1250 - 3
{Pasteurellosis in human pathology}; Roccasalva M et al.; Pasteurella are common bacteria among healthy animals . Humans usually are infected by dog and cat bites or scratches . Besides, local skin infection, Pasteurella may spread, in some cases, to lungs, joints, bones or, less frequently, to other organs.

Avian Dis, 1990 Oct-Dec, 34(4), 928 - 33
Fowl cholera in California multiplier breeder turkeys: 1985-86; Campi TW et al.; One hundred twenty-nine multiplier breeder turkey flocks on 45 premises in California were monitored for outbreaks of fowl cholera (FC) (Pasteurella multocida) for 1 year (Aug . 1, 1985, through July 31, 1986) . Fourteen (11%) flocks on 10 (22%) premises experienced outbreaks . Nine (64%) outbreaks occurred in the fall or winter . FC-outbreak flocks had significantly shorter lay cycles (24.6 weeks vs . 27.9 weeks) and correspondingly lower total egg production per hen (84 eggs vs . 103 eggs) than non-outbreak flocks . A case-control investigation was performed on 11 FC-outbreak (case) flocks, and nine non-outbreak (control) flocks . Case flocks were located statistically closer to other livestock species than were control flocks (0.28 miles vs . 0.68 miles) and were more likely to utilize on-farm disposal of dead birds.

Avian Dis, 1990 Oct-Dec, 34(4), 888 - 92
Serum resistance as an indicator of virulence of Pasteurella multocida for turkeys; Morishita TY et al.; Wildlife isolates of Pasteurella multocida, whose virulence for turkeys had previously been determined by intravenous inoculation, were characterized regarding their ability to survive incubation in fresh non-immune turkey serum . The relative virulence of the isolates was significantly associated with their ability to resist the bactericidal power of the serum as determined by standard plate counts following incubation . Organisms with a high survival value were more virulent; those with a low survival value were less virulent . A statistical model was specified and was successfully used to predict relative virulence of the P . multocida isolates . This method of assaying serum resistance was rapid, repeatable, and practical and could be performed with minimal laboratory equipment . Also studied was the serum resistance of seven serotype 3, 4 isolates obtained from the lungs of M9-vaccinated turkeys from seven flocks experiencing increased mortality due to fowl cholera . These isolates were shown to be identical to the M9 vaccine by restriction endonuclease analysis of chromosomal DNA . Six of the seven isolates had higher serum survival values than the original M9 vaccine.

Nippon Juigaku Zasshi, 1990 Oct, 52(5), 915 - 21
Prevalence and characterization of Pasteurella multocida in rabbits and their environment in Japan; Kawamoto E et al.; Prevalence and some properties of Pasteurella multocida in rabbits kept at laboratory animal facilities and commercial rabbitries, and in their environment were investigated . A total of 1,147 nasal swab samples from 1,147 rabbits and 126 samples from their environment were subjected to the isolation of P . multocida . The bacteria were isolated from 199 (29.8%) of 668 rabbits in laboratory animal facilities and from 1 (0.2%) of 479 rabbits in the rabbitries . Isolation rate of P . multocida was low (0.9%) or high (44.9%) in the facilities with or without the monitoring for the presence of the bacteria, respectively . The highest rate of the isolation from rabbits was recorded at 10 to 12 months of their housing time . Thirty-nine cultures (31.0%) of air and the surfaces of floors, tips of water bottles, and cages were positive for P . multocida and isolation rate of the bacteria was high (78.6%) in the air . Biological and biochemical properties of the isolates were identical except for indole production and raffinose fermentation . The isolates were susceptible to antibiotics tested except for clindamycin, serologically similar in the gel-diffusion precipitin test and weakly virulent for mice . The present results suggested that these P . multocida isolates were the causal agent of rabbits rhinitis (snuffles) in Japan.

Vet Q, 1990 Oct, 12(4), 212 - 20
In vitro activity of flumequine in comparison with several other antimicrobial agents against five pathogens isolated in calves in The Netherlands; Mevius DJ et al.; The in vitro activity of flumequine in comparison with several other drugs was tested against 17 P . multocida, 16 P . haemolytica, 21 S . dublin, 21 S . typhimurium and 21 E . coli strains, isolated in (veal) calves in the Netherlands . The MIC50 of flumequine for the respective pasteurellas was 0.25 and 1 microgram/ml, for the salmonellas and E . coli 0.5 micrograms/ml . In comparison with flumequine, enrofloxacin and ciprofloxacin showed higher in vitro activity, with MIC50 less than or equal to 0.008 micrograms/ml for ciprofloxacin . Decreased susceptibility of the pasteurellas was found for kanamycin, neomycin, streptomycin, gentamicin, oxytetracycline and doxycycline . The MIC50 of minocycline for P . multocida was 0.5 micrograms/ml and there was no cross resistance with the other tetracyclines . P . multocida was very susceptible to ampicillin (MIC50 less than or equal to 0.03 micrograms/ml), P . haemolytica, however, was 100% resistant to this drug . Both pasteurellas were susceptible to cephalothin and approximately 50% of the strains of both bacteria were resistant to chloramphenicol . The MIC50 of either spiramycin or tylosin was greater than or equal to their respective breakpoint-MIC values . Both pasteurellas were susceptible to the combination of trimethoprim and sulphamethoxazole . However, for P . multocida, the addition of sulphamethoxazole to trimethoprim had no synergistic effect on its MIC . In comparison with trimethorpim, aditoprim was less potent . Therefore only P . multocida was susceptible to aditoprim.

Lab Anim, 1990 Oct, 24(4), 341 - 4
In vivo activity of orally administered antibiotics and chemotherapeutics against acute septicaemic pasteurellosis in rabbits; Okerman L et al.; Different antibiotics and chemotherapeutics were tested for therapeutic efficacy in rabbits, in an experimental model using a Pasteurella multocida strain which causes hyperacute septicaemia in this animal species . Only enrofloxacin, administered in the drinking water at a concentration of 50-100 mg/l cured the rabbits, provided that a daily intake of 5 mg/kg body weight was achieved . The other drugs tested (tetracycline, spiramycin, erythromycin and a combination of sulfamerazine with trimethoprim), at doses recommended for rabbits, showed little or no activity at all, with the exception of chloramphenicol, which was only partially effective.

Can J Vet Res, 1990 Oct, 54(4), 422 - 6
Restriction endonuclease analysis of porcine Pasteurella multocida isolates from Quebec; Harel J et al.; We have used restriction endonuclease analysis (REA) of genomic DNA to classify porcine Pasteurella multocida isolates with similar capsular and somatic serotypes, and to monitor the distribution of isolates from 12 different herds in Quebec . Within herds, P . multocida isolates of similar capsular and somatic serotypes showed similar REA fingerprints . Between herds, some isolates had similar REA fingerprints . However, differences in REA enabled subtyping of many P . multocida isolates with the same antigen types . Our data indicate that REA would enable accurate epidemiological typing of P . multocida in conjunction with classical capsular and somatic typing.

Can J Vet Res, 1990 Oct, 54(4), 415 - 21
Hematological changes in calves exposed to a mixture of lipopolysaccharide and crude leukotoxin of Pasteurella haemolytica; Bowersock TL et al.; The purpose of this investigation was to determine if culture supernatants of Pasteurella haemolytica containing crude leukotoxin and lipopolysaccharide (CLCL) causes disseminated intravascular coagulopathy (DIC) when injected into calves . The effect of intraduodenal (ID) exposure followed by a subsequent subcutaneous (SC) inoculation of either heat-treated or untreated CLCL was evaluated . The relative contribution of the crude leukotoxin and lipopolysaccharide (LPS) to the virulence of P . haemolytica was evaluated . One group of calves received an ID inoculation of CLCL followed two weeks later by a SC inoculation of CLCL; one group received an ID inoculation of tissue culture medium followed two weeks later by a SC inoculation of CLCL; and a third group received an ID inoculation of CLCL followed two weeks later by a SC inoculation of heat-treated CLCL . Hematological parameters used to evaluate DIC included white cell count, platelet count, neutrophil number, fibrinogen, fibrin degradation products, one stage prothrombin time (OSPT), activated partial thromboplastin time, body temperature and clinical signs . Each parameter was measured in calves at 0, 2, 4, 6, 12 and 24 h following the SC inoculation of CLCL . Each group had significant changes over time in all parameters except body temperature . Calves that received a SC inoculation of heat-treated CLCL had smaller changes in all parameters except OSPT compared to the other groups . Results suggest that the LPS and leukotoxin of P . haemolytica exert additive effects on the coagulation cascade and number of peripheral leukocytes, and that the ID inoculation of CLCL does not affect the response of calves to a SC inoculation of toxin.

Vet Microbiol, 1990 Oct, 25(1), 67 - 75
Phenotypical and genotypical characteristics of paired isolates of Pasteurella multocida from the lungs and kidneys of slaughtered pigs; Buttenschon J et al.; Twenty-eight strains of Pasteurella multocida were isolated from 12 Danish and two Canadian abattoir pigs . Fourteen strains were isolated from pulmonary inflammatory lesions, and 14 strains were isolated from kidneys of the same animals . Phenotypical and genotypical characteristics of the strains were evaluated with a view to determine if P . multocida isolated from kidneys might have been disseminated from the lungs . All field strains were capsular type A . The biochemical reactivity in the API-20E and API-ZYM commercial test-kits was uniform with the exception of alpha-glucosidase activity which was present at low levels in only ten of the strains . One strain was markedly serum sensitive, six strains slightly sensitive and the remaining were serum resistant . The peptide patterns obtained by polyacrylamide gel electrophoresis of whole cell proteins of the strains were very uniform with the exception of differences in intensity of bands in the 38 and 34 kD regions . The pattern of oligonucleotides obtained after electrophoresis of total genomic DNA digested with BamHI showed that the paired isolates had identical patterns in eight of the 14 animals . It is therefore likely that isolates from kidney lesions represent blood borne dissemination from primary pulmonary lesions.

Jikken Dobutsu, 1990 Oct, 39(4), 549 - 55
Determination of an antigen suitable for enzyme-linked immunosorbent assay of the antibody to Bordetella bronchiseptica in guinea pigs; Sakurai Y et al.; To establish an enzyme-linked immunosorbent assay (ELISA) technique for the serological diagnosis of infections caused by Bordetella bronchiseptica (B . bronchiseptica) in guinea pigs, the authors recently assessed the usefulness of three antigen preparations derived from the bacterial cell components: sonication antigen (S-Ag), cell surface antigen (C-Ag) and lipopolysaccharide antigen (L-Ag) . The use of S-Ag for ELISA resulted in the most sensitive detection of the antibody to B . bronchiseptica from guinea pig sera immunized with killed bacteria and sera derived from naturally infected guinea pigs . Like C-Ag, S-Ag was highly specific, showing no cross-reactivity with Pasteurella multocida . Assessment of antibody formations in animals with experimentally induced infection using the three antigen preparations revealed that the antibody to S-Ag was formed earlier than antibodies to the other two antigen preparations following growth of the bacterium in the lungs . These results indicate that ELISA with S-Ag as an antigen is a useful tool for the serological diagnosis of infection by B . bronchiseptica.

Am J Vet Res, 1990 Oct, 51(10), 1629 - 34
Immune response to pulmonary injection of Pasteurella haemolytica-impregnated agar beads followed by transthoracic challenge exposure in goats; Purdy CW et al.; A method of inducing Pasteurella haemolytica serotype 1 (Ph1) lung infection in goats, using low numbers of bacteria and without impairing host immunity, was developed . Two trials were conducted . Results of trial 1, using 10 principals (Ph1 agar beads) and 6 controls (agar beads alone), indicated that Ph1 organisms imbedded in agar beads could survive host lung defenses for 32 days . Results of trial 2 indicated that lung immunity in the inoculated goats (principals) was high and they were more protected than controls against a transthoracic challenge of Ph1 (1.18 x 10(7) colony-forming units) injected into a lung of each goat on posttreatment day 35 . When comparing challenge-exposed principals with controls, the controls developed rectal temperatures above normal for a longer time, duration of anorexia was longer, and signs of depression were seen . The controls developed large areas of consolidated lung tissue, more Ph1 isolates were recovered from nasal turbinates and lung tissue, and higher Ph1 concentrations were found in the lungs . The serum Ph1 indirect hemagglutination antibody titers in the principals of both trials increased, compared with titers in controls . Principal goats in trial 2 had higher Ph1 indirect hemagglutination antibody titers after injection of Ph1-impregnated agar beads and less severe lung lesions after challenge exposure than did controls . The small pneumonic consolidated lesions in the principals, compared with extensive lesions in controls after Ph1 challenge exposure, indicated a high degree of immunity after exposure to Ph1 organisms imbedded in agar beads.

Avian Dis, 1990 Oct-Dec, 34(4), 1005 - 8
Pasteurella haemolytica as a co-pathogen in pullets and laying hens; Shaw DP et al.; Pasteurella haemolytica was isolated from internal organs of laying hens and pullets of four flocks in which five incidents of increased mortality had occurred . There was inflammation of the trachea in all cases, and infectious laryngotracheitis virus was identified in three of the incidents . Rapid response to antimicrobial therapy was seen in two out of three outbreaks in the pullets . P . haemolytica was regarded as a significant secondary invader in these cases.

Avian Dis, 1990 Oct-Dec, 34(4), 958 - 63
Characterization of Pasteurella multocida mutants of low virulence; Lee MD et al.; Ten temperature-sensitive mutants of the Clemson University (CU) vaccine strain of Pasteurella multocida have been developed and were characterized by phenotypic attributes such as carbohydrate fermentation, antibiotic resistance, and membrane protein profiles . Some mutants were found to have lost the ability to utilize some substrates, notably xylose and gluconate, whereas others were able to ferment additional carbohydrates such as arabinose and rhamnose . CU was found to be resistant to sulfisoxazole, of intermediate resistance to bacitracin, and sensitive to rifampin; the sensitivity to these three antibiotics varied among the mutant strains, but 60% were resistant to rifampin . Membrane protein profiles demonstrated some changes in major bands, and there was variation in 50% of the mutants in proteins in the 31 kilodalton range . All strains were assayed for the presence of several virulence factors, and many were found to produce siderophore and to exhibit some degree of complement resistance.

Am J Vet Res, 1990 Oct, 51(10), 1635 - 9
Pasteurella haemolytica lipopolysaccharide-induced arachidonic acid release from and neutrophil adherence to bovine pulmonary artery endothelial cells; Paulsen DB et al.; Bovine pulmonary artery endothelial cells (BPAEC) were labeled with 3H-arachidonic acid . Exposure of the labeled BPAEC to Pasteurella haemolytica lipopolysaccharide (LPS) resulted in a time- and dose-dependent release of radioactivity . The release was inhibited by 5 mM indomethacin, but inhibition was not caused by less than or equal to 500 microM indomethacin or hydrocortisone, which suggests that the release was caused primarily by a mechanism other than cyclooxygenase or phospholipase A2 metabolism of arachidonic acid . Pasteurella haemolytica LPS also caused increased adherence of bovine neutrophils to BPAEC through independent effects on both cell types . The increased adherence was inhibited by treatment of either cell type with cycloheximide or actinomycin D prior to LPS exposure, indicating that de novo protein synthesis was required in both cell types to promote the LPS-induced adherence . Lipopolysaccharide may be an important factor in neutrophil-mediated effects in pneumonic pasteurellosis by causing increased neutrophil adherence and, thus, the vascular sequestration of neutrophils . Together, these experiments provide additional evidence for the involvement of LPS in pneumonic pasteurellosis . Moreover, they provide evidence of LPS-induced endothelial activation, which could have broad ramifications in the inflammatory and immune responses of pneumonic pasteurellosis.

Kansenshogaku Zasshi, 1990 Sep, 64(9), 1200 - 4
{Human respiratory tract infection by Pasteurella multocida subsp . multocida presumably derived from the cat}; Arashima Y et al.; Pasteurella multocida is a Gram-negative short rod-shaped bacteria that has been recognized as a pathogen of hemorrhagic septicemia and fowl cholera in the veterinary medicine . Infections by this microorganism as seen in the foreign literature vary widely from local infections due to bites and scratches by animals to general infections such as infections of the respiratory tract, sepsis, and meningitis . In Japan, reported cases of P . multocida infections are predominantly local infections, followed by respiratory infection . Recently, death of diabetic patients due to septicemia by this pathogen has also been reported . In this study, we experienced a case of respiratory tract infection in which the pathogen P . multocida subsp . multocida was suggested to have been transmitted from a pet cat by the agreement of the serotype of the bacterial isolates between the patient and the cat . This case was evaluated from the zoonotic viewpoint . The patient was a 68-year-old male who had been followed up since 1982 with a diagnosis of bronchiectasis . After his referral to our hospital, P . multocida subsp . multocida was isolated from his bloody sputum and, then, from the cat kept by the patient . The tow isolates were identical in terms of the biochemical properties, drug susceptibility profile, and serotype (-:1), and the derivation of P . multocida subsp . multocida infection from cat was established for the first time in this report . The incidence of P . multocida infections is increasing in Japan, and particular attention is considered to be needed about these conditions as zoonoses as indicated in "Preventive Measures against Zoonoses Derived from Pet Animals (Dog, Cat)", an official communication from the Ministry of Health and Welfare to related institutions in 1989 . Also, to check whether the patient keeps any pet at the clinical inquiry is a practice of bacteriological importance in all fields of medicine.

Dtsch Tierarztl Wochenschr, 1990 Sep, 97(9), 364 - 6
{Atrophic rhinitis in swine and other animal species}; Frymus T; Evidence that cattle, goats and rabbits may suffer from natural diseases equivalent to porcine atrophic rhinitis is presented . Etiology and course of the progressive (enzootic) and non-progressive (sporadic) forms of atrophic rhinitis in pigs are discussed and compared with known data about similar diseases in other animals . It seems that atrophic rhinitis caused by toxigenic strains of Pasteurella multocida may be a disease of different animal species.

Zentralbl Veterinarmed B, 1990 Sep, 37(7), 520 - 31
{Electron microscopic studies of mucosal extirpates of rabbits after after in vitro contact with Pasteurella multocida subsp . multocida strains}; Botcher L et al.; In vitro experiments of adhesion and colonisation of mucosal surface fragments (nose, trachea) from freshly killed rabbits with four strains of Pasteurella multocida subsp . multocida with different types of capsule antigen (A, D, without capsule) showed the following results: Above all the capsule serovar A strain, producing a capsule of hyaluronic acid and fimbria, were able to adhere and to form microcolonies on the mucosal surface . Microvilli of epithelial cells and mucus producing cells were recognized as the place of adhesion . The formation of microcolonies occurred with a destruction of the kinocilia, which was caused by a bacteria free culture filtrate as well.

Am J Vet Res, 1990 Sep, 51(9), 1395 - 9
Bovine recombinant granulocyte-macrophage colony-stimulating factor enhancement of bovine neutrophil functions in vitro; Reddy PG et al.; Neutrophils were purified from blood of dexamethasone-treated (0.04 mg/kg of body weight) and untreated calves . Cells were untreated (controls) or cultured in media containing 5 or 10 ng of bovine recombinant granulocyte-macrophage colony-stimulating factor (rbGM-CSF)/ml for 10 to 12 hours before being tested for various functions . Dexamethasone treatment of calves decreased luminol-dependent chemiluminescence, decreased phagocytosis of Pasteurella multocida and several Staphylococcus spp by various degrees, and decreased antibody-dependent cell-mediated cytotoxicity against bovine herpesvirus-infected cells by 26 to 32% . The percentage phagocytosis of coagulase-positive S aureus and S intermedius was higher than that of coagulase-negative S epidermidis for neutrophils from all calves . Culture of neutrophils with rbGM-CSF significantly increased (P less than 0.05) all of the aforementioned functions, compared with control neutrophils; however, rbGM-CSF-induced increases in function tended to be higher in neutrophils from dexamethasone-treated calves than in neutrophils from untreated calves.

Vet Med (Praha), 1990 Sep, 35(9), 537 - 46
{Nonspecific immunostimulating activity of Bordetella bronchiseptica bacterin in tests on mice and calves}; Toman M et al.; Three experimental models were used to verify the effectiveness of immunostimulant preparations of microbial origin . Of the four microbial species, used in the tests with the stimulation of mice against subsequent infection with the virulent strain of Pasteurella multocida, the highest resistance-increasing power was recorded in Bordetella bronchiseptica . There were large differences in stimulation activity between its strains, ranging from those with a low activity up to strain 6229, which increased the LD50 of the infected mice to a level 72 times as high as in the control . The differences in the survival of the mice also varied within the range between immunostimulation and infection, the best effect being obtained when the mice were stimulated 48 h before the infection . No significant difference was recorded between the use of the bacterin of B . bronchiseptica alone or B . bronchiseptica bacterine with oil adjuvant . The immunostimulant activity of B . bronchiseptica was also demonstrated in the model of sublethally irradiated mice in which the preventive administration 24 h before irradiation led to earlier and faster regeneration of the lymphoid tissue: this led to a higher weight of the spleen, to an increase in the number of peripheral leucocytes, and increased activity of chemiluminiscence six days after irradiation . The bacterine of B . bronchiseptica was also used at different concentrations and in combinations with other substances to stimulate two-month-old clinically healthy calves . The most pronounced effect was obtained after the administration of B . bronciseptica bacterine with oil adjuvant and after administration of the same substances together with vitamin A: twenty-four hours after these treatments there was an increased number of peripheral leucocytes and after 2-4 days an increased activity was observed in the MSHP particle phagocytosis test and in the chemiluminiscence test . The activity of lymphocytes in the blastic transformation test was insignificantly increased seven days after stimulation.

Vet Microbiol, 1990 Aug, 24(2), 143 - 53
The humoral immune response of lambs experimentally infected with Mycoplasma ovipneumoniae; Thirkell D et al.; Using sera from lambs experimentally infected with Mycoplasma ovipneumoniae and Pasteurella haemolytica, the development of a good humoral immune response to M . ovipneumoniae was detected by ELISA . The antibody titres peaked 41 days post-infection and good antibody titres were maintained over the 16-week experimental period . Immunoblotting revealed that antibodies to specific antigens appeared in the sera in a sequential manner, some being seen shortly after infection and others developing only after a substantial time lag . Antibodies were raised against almost all the major antigens detected in one laboratory strain (956/2) and against all antigens previously shown to be conserved in 22 Scottish field isolates of M . ovipneumoniae.

Tierarztl Prax, 1990 Aug, 18(4), 365 - 76
{Epizootiology, clinical aspects and therapy of Pasteurella multocida infection in bird patients after cat bite}; Korbel R; Since early 1986, fatal cases of Pasteurella multocida infection following cat bites have been seen regularly among avian patients at our institute . The problems of the epizootiology of this infection are discussed on the basis of research during the last three and a half years . By evaluation of collected data from clinical examinations, autopsies, bacteriological and biochemical diagnosis of isolated strains from birds and cats the possibility of transmission via cat bite is discussed as well as the status of cats and birds in an epizootic chain . Even birds with trivial wounds caused by cats must be classified as emergency patients . The risk of an infection after a cat bite is about 56% . For treatment of a Pasteurella multocida infection Doxycycline should be used.

J Clin Microbiol, 1990 Aug, 28(8), 1858 - 61
Specificity of DNA probes for the detection of toxigenic Pasteurella multocida subsp . multocida strains; Kamps AM et al.; Five DNA probes directed against different regions of the gene that encodes the dermonecrotic toxin of Pasteurella multocida subsp . multocida were examined for their ability to identify toxigenic P . multocida subsp . multocida strains . The specificities of the probes were studied with 96 strains of P . multocida subsp . multocida and 22 strains of 11 other bacterial species . Results of colony hybridization assays using these probes indicated that two of the five probes have potential diagnostic value.

Am J Vet Res, 1990 Aug, 51(8), 1161 - 6
Comparison of DNA:DNA homology and enzymatic activity between Pasteurella haemolytica and related species; Bingham DP et al.; A commercially available microbiological identification system and DNA:DNA hybridization were used to determine relationships between and within serovars 1-13 of Pasteurella haemolytica, and between P haemolytica and P multocida and 4 species of Actinobacillus . All serovars of P haemolytica that belonged to biovar A were related with mean DNA homology of 78%, whereas all serovars of P haemolytica that belonged to biovar T were related to each other with mean DNA homology of 90% . The DNA:DNA hybridization between strains of biovars A and T ranged from 3 to 13%, indicating little or no genetic relationship between the 2 biovars of P haemolytica . The DNA homology between all serovars of P haemolytica and other species of non-P haemolytica bacteria tested (P multocida and actinobacilli) was less than 14%, suggestive of essentially no genetic relationship of P haemolytica with the ATCC reference strains of the genus Pasteurella or the genus Actinobacillus . Enzymatic differences were observed between P haemolytica and the other non-P haemolytica bacteria tested; however, the microbiological identification system that uses enzymatic reactions could not distinguish among biovars of P haemolytica . Results of this research support other data that suggest that biovars A and T of P haemolytica should be classified as separate species, but do not support the inclusion of either biovar A or T within the genus Actinobacillus.

Vaccine, 1990 Aug, 8(4), 315 - 20
Protective effect of inactivated Pasteurella haemolytica bacterin challenged in bovine herpesvirus-1 experimentally infected calves; Jericho KW et al.; Formalin-inactivated and sonicated Pasteurella haemolytica bacterins were prepared from 1 h cultures of bacterial pellets in RPMI-1640 medium containing 7% fetal calf serum . The bacterial pellets were obtained from logarithmic phase growth of the organism by centrifugation . The protective effect of the vaccine was evaluated in 43 specific-pathogen-free Hereford crossbred calves and yearlings in three experiments . Cattle were either single vaccinated or boosted via three routes; intratracheally (i.t.), intranasally (i.n.) or intramuscularly (i.m.), using low or high doses . The two low-dose groups were also given supernatant by the same routes and volume as the bacterin . Cattle were challenged by P . haemolytica in aerosol at 24 or 39 days after last vaccination . To enhance the susceptibility of the cattle to this challenge, the cattle were exposed to bovine herpesvirus-1 aerosol 4 days before the bacterial challenge . The extent of pneumonia was significantly less in three groups of cattle (i.n.-i.n.,i.m.-i.n.,i.m.-i.m.) boosted with high dose of the bacterin than in the controls . Protection was observed when challenge isolates were heterologous or homologous to the isolates used to prepare the bacterins . It was also observed that the level of complement fixing antibody or anticytotoxin activity to P . haemolytica did not correlate with the degree of protection.

Nippon Juigaku Zasshi, 1990 Aug, 52(4), 677 - 88
Clinical and pathological effects of the dermonecrotic toxin of Bordetella bronchiseptica and Pasteurella multocida in specific-pathogen-free piglets; Elias B et al.; The role of dermonecrotic toxin (DNT) of Bordetella bronchiseptica and Pasteurella multocida, purified by repeated chromatography in Sephacryl S-200 gel, in the pathogenesis of atrophic rhinitis (AR) of swine was studied bacteriologically, clinically and pathologically . Two-week-old specific pathogen-free (SPF) piglets were parenterally treated with 30 micrograms of DNT 3 times at 2-day interval and 7-week-old piglets were treated with 15 micrograms of DNT twice a week for 5 weeks . In 2- to 3-week-old piglets, both B . bronchiseptica DNT and P . multocida DNT produced nasal turbinate lesions with similar severity, characterized by damage of the cilia, epithelial metaplasia, intensive proliferation of osteoblasts, regressive changes, and diffuse osteocytic osteolysis . In 7- to 12-week-old piglets, treatment with B . bronchiseptica DNT failed to produce progressive changes in the nasal turbinates . Histopathological examination revealed osteogenic processes and osteoid synthesis besides the proliferation of osteoblasts and mild osteocytic osteolysis . Moreover, severe gross pathological lesions developed in the stomach, liver, kidneys, and lymphoid organs . The piglets' appetite and body weight gain gradually decreased during the DNT treatment and in the last week when the toxic signs appeared . Treatment of 7- to 12-week-old piglets with P . multocida DNT resulted in progressive AR . Histopathologically, diffuse osteocytic osteolysis was observed in the nasal turbinates . Neither clinical signs nor pathological lesions of the visceral organs developed in these piglets . The authors emphasize that the DNT of B . bronchiseptica basically differs from that of P . multocida in biological properties, though there are certain similarities between the DNTs.

Singapore Med J, 1990 Aug, 31(4), 400 - 2
Pasteurella multocida osteomyelitis of the cervical spine in a patient on chronic haemodialysis; Tan CC et al.; Osteomyelitis due to Pasteurella multocida has been frequently documented but virtually all previous cases have resulted from direct inoculation of the organism or contiguous spread of local infection, following animal bites or scratches . Infections often occur in patients with serious underlying illnesses . Haematogenous osteomyelitis due to P multocida has very rarely been reported particularly in patients with chronic renal failure . We describe a patient on chronic haemodialysis who developed an acute febrile illness, two months following a monkey bite, caused by haematogenous cervical vertebral osteomyelitis due to P multocida.

Zentralbl Veterinarmed A, 1990 Aug, 37(7), 525 - 36
The effect of stress on host defense system and on lung damage in calves experimentally infected with Pasteurella haemolytica type A1; Binkhorst GJ et al.; This paper describes the influence of stress, immediately before a massive inoculation of a log-phase P . haemolytica A1 culture in brain-heart-infusion broth by fiberoptic bronchoscopy in 5 months old conventional calves . Differences in phagocytic cell function and numbers, lung function and lung tissue damage between stressed and non-stressed, infected calves were studied . Compared with the non-stressed calves before infection, the superoxide generation by blood polymorphonuclear leucocytes of the stressed animals was markedly reduced immediately after a 2 hours stress period, but it recovered within 3 days . The total numbers of phagocytic cells, harvested from lung lavage fluid 3 days after inoculation were twice as high in the non-stressed calves than in the stressed calves . In contrast, no differences in pulmonary lesions and functions were found between stressed or non-stressed calves . The role of several stress factors on infiltration and metabolic response of polymorphonuclear leucocytes in P . haemolytica infections and the effects of bacterial endotoxin and leukotoxin on alveolar and vascular injury are discussed.

Trop Anim Health Prod, 1990 Aug, 22(3), 185 - 94
Persistence of the carrier status in haemorrhagic septicaemia (Pasteurella multocida serotype 6:B infection) in buffaloes; de Alwis MC et al.; Fifty-seven young buffaloes were experimentally infected or naturally exposed to haemorrhagic septicaemia (HS) . Of these animals 32 became immune carriers . They were observed in groups for periods up to 360 days to monitor the appearance of pasteurellae in the nasopharynx and antibody status . In most animals pasteurellae appeared in the nasopharynx for a short period initially and disappeared . The organism reappeared intermittently and the longest observed period of reappearance was 215 days after exposure . All animals showed rising antibody titres with a peak lasting for 150 to 180 days and declining thereafter . Pasteurellae persisted in the tonsils and were isolated from 20 out of 27 carriers after slaughter . The longest period when isolation was made after slaughter was 229 days . The organism lodged in the tonsils was unaffected by antibacterial therapy using drugs to which the organism displayed in vitro sensitivity . It is concluded that in HS, carrier animals exist in an active as well as a latent state, the former appearing for short intermittent periods between long latent periods, when pasteurellae continue to remain in the tonsils which constitute a long-term reservoir.

Vaccine, 1990 Aug, 8(4), 358 - 68
Epitope specificity of the protective immune response induced by individual bovine herpesvirus-1 glycoproteins; van Drunen Littel-van den Hurk S et al.; Affinity-purified bovine herpesvirus-1 (BHV-1) glycoproteins gI, gIII and gIV, as well as a virus-free BHV-1-infected cell lysate were injected intramuscularly into seronegative calves . All immunized animals developed specific serum-neutralizing antibodies and they were fully protected from disease, using a BHV-1/Pasteurella haemolytica challenge model . After challenge, viral replication in the nasal passages was significantly reduced in animals vaccinated with gIV (10,000-fold) or BHV-1-infected cell lysate (450,000-fold) but just slightly reduced in animals immunized with gI (500-fold) or gIII (25-fold) . All of the known epitopes of the glycoproteins were retained during the affinity-purification or preparation of the cell lysate . The high level of protection induced by gIV and the virus-infected cell lysate in particular indicates the potential of glycoprotein gIV as a subunit vaccine, ideally in combination with component(s) from the cell lysate, which may mediate cellular immune responses.

Vet Rec, 1990 Jul 28, 127(4), 83 - 6
Screening pig herds for toxigenic Pasteurella multocida and turbinate damage in a health scheme for atrophic rhinitis; Goodwin RF et al.; The Pig Health Control Association launched a health scheme for atrophic rhinitis in 1978 . For several years pig herds were monitored by scoring the degree of turbinate damage and by clinical inspections . When laboratory facilities became available for detecting toxigenic Pasteurella multocida, nasal swabs were taken from pigs in Association herds during 1988 and 1989 to determine whether the organism was present . Sows were screened routinely and in the worst affected herds, sucklers and weaners were also swabbed . In 12 of 19 herds with consistently low snout scores toxigenic P multocida were not isolated, and in 15 herds which developed higher snout scores with time toxigenic P multocida were also not found . Eleven herds had never been listed by the Association, either because their snout scores were consistently high or because they had received importations of stock from herds with high snout scores; of six of these herds with the most persistently high snout scores five showed varying degrees of the clinical signs of atrophic rhinitis, but none of the six showed evidence of infection with toxigenic P multocida, and the organism was not found in the other five herds in the group . There seems to be an overlap between the clinical and gross pathological signs of atrophic rhinitis seen in some herds not infected with toxigenic P multocida and the mild and spasmodic signs of atrophic rhinitis seen in some herds which are substantially infected with the organism.

Vet Rec, 1990 Jul 21, 127(3), 64 - 6
Mycoplasmas and acholeplasmas isolated from ducks and their possible association with pasteurellas; Tiong SK; Two hundred and sixty-three cases of clinically diseased ducks of all ages were examined for the presence of mycoplasmas . Mycoplasmas and acholeplasmas belonging to more than eight serogroups were cultured from 68 of them, and comprised 12 M anatis, one M columbinasale, two M gallinaceum, two M gallinarum, nine M synoviae, three unidentified Mycoplasma species, 37 Acholeplasma laidlawii and one unclassified acholeplasma belonging to each of serogroups 7 and 8 . They were identified by biochemical characterisation, disc growth inhibition and agar gel diffusion tests . Fifty-three (78 per cent) of the isolates occurred with species of Pasteurella: 33.8 per cent with Pasteurella anatipestifer, 32.4 per cent with P multocida and 11.8 per cent with both P anatipestifer and P multocida . Nine of the isolates (13.2 per cent) were in pure culture and six (8.8 per cent) with other agents . Of the ducks negative for mycoplasmas 33.3 per cent were infected with P anatipestifer, 25.1 per cent with P multocida and 14.4 per cent with both P anatipestifer and P multocida . There was no correlation between the infections with mycoplasmas and P anatipestifer but there was a weak association between the infections with mycoplasmas, especially M anatis and P multocida.

J Biol Chem, 1990 Jul 15, 265(20), 11841 - 8
Pasteurella multocida toxin, a potent mitogen, stimulates protein kinase C-dependent and -independent protein phosphorylation in Swiss 3T3 cells; Staddon JM et al.; Pasteurella multocida toxin, either native or recombinant (rPMT), is an extremely effective mitogen for Swiss 3T3 cells and acts at picomolar concentrations (Rozengurt, E., Higgins, T . E., Chanter, N., Lax, A . J., and Staddon, J . M . (1990) Proc . Natl . Acad . Sci . U . S . A . 87, 123-127) . Here, we show that similar concentrations of rPMT markedly stimulated the phosphorylation of an acidic 80-kDa protein in {32P}Pi-labeled Swiss 3T3 cells . Co-migration on one- and two-dimensional gels and phosphopeptide analysis indicated that this phosphoprotein was indistinguishable from 80K, a known protein kinase C substrate . In parallel cultures, the stimulation of 80K phosphorylation by rPMT (5-10-fold) was comparable to that induced by bombesin or phorbol dibutyrate (PBt2) . However, the increase in phosphorylation by rPMT occurred after a pronounced lag period (1-3 h, depending upon the concentration of rPMT) in contrast to the relatively immediate stimulation by PBt2 or bombesin . Early, but not late, addition of either PMT antiserum or the lysosomotrophic agent methylamine selectively inhibited 80K phosphorylation in response to rPMT . 80K phosphorylation persisted after removal of free toxin and was not inhibited by cycloheximide . It appears that rPMT enters the cells via an endocytotic pathway to initiate and perpetuate events leading to 80K phosphorylation . rPMT, like PBt2, also stimulated the phosphorylation of 87-kDa and 33-kDa proteins in Swiss 3T3 cells . Phosphorylation of the 80K and 87-kDa proteins by rPMT or PBt2 were greatly attenuated in cells depleted of protein kinase C . In contrast, phosphorylation of the 33-kDa protein by rPMT, but not by PBt2, persisted in the absence of protein kinase C . rPMT, like bombesin, caused a translocation of protein kinase C to the cellular particulate fraction . The toxin enhanced the cellular content of diacylglycerol . rPMT also caused a time- and dose-dependent decrease in the binding of 125I-epidermal growth factor to its receptor which was blocked by methylamine and dependent only in part upon the presence of protein kinase C . We conclude that rPMT stimulates protein kinase C-dependent and -independent protein phosphorylation in Swiss 3T3 cells.

Vet Pathol, 1990 Jul, 27(4), 254 - 60
Septicemia in vaccinated and nonvaccinated turkeys inoculated with Pasteurella multocida serotype A:3,4; Prantner MM et al.; Sixty-four, 10-week-old turkeys were inoculated with a highly virulent field isolate (86-1913) of Pasteurella multocida serotype A:3,4 by an oculo-nasal-oral route . Inoculated turkeys were examined at 4, 8, 16, 20, and 24 hours post-inoculation for bacteremia and histologic lesions . Bacteremia was detected in one of six turkeys 8 hours after inoculation and in four of six turkey poults at 16 hours post-inoculation . Pasteurella multocida was isolated from the spleens of two turkeys at 8 hours and from the spleens of all six poults 16 hours after inoculation . Peak concentrations of P . multocida reached 10(9) colony forming units per ml of blood . At 4 to 8 hours post-inoculation, isolate 86-1913 produced a fibrinopurulent bronchopneumonia followed by severe pulmonary necrosis, pleuritis, vasculitis; and, at 16 to 24 hours post-inoculation numerous extracellular bacteria were observed . Hepatic lesions included focal heterophil aggregates 8 hours after inoculation; these progressed to hepatic necrosis . Numerous extracellular bacteria within sinusoids were present 16 to 24 hours after inoculation . At 16 to 24 hours post-inoculation, there was degeneration of periarteriolar reticular cells in the spleen; these cells progressed to coalescing coagulative splenic necrosis with extracellular bacterial colonies . A second group of 41, 10-week-old turkeys, previously vaccinated with the Clemson University strain of P . multocida serotype A:3,4, were challenged with isolate 86-1913.(ABSTRACT TRUNCATED AT 250 WORDS)

Infect Immun, 1990 Jul, 58(7), 2091 - 7
Iron acquisition in Pasteurella haemolytica: expression and identification of a bovine-specific transferrin receptor; Ogunnariwo JA et al.; Seven type 1 field isolates of Pasteurella haemolytica were screened for their ability to use different transferrins as a source of iron for growth . All seven strains were capable of using bovine but not human, porcine, avian, or equine transferrin . A screening assay failed to detect siderophore production in any of the strains tested . Iron-deficient cells from these strains expressed a binding activity, specific for bovine transferrin, that was regulated by the level of iron in the medium . Inhibition of expression by translation and transcription inhibitors suggested that iron regulation was occurring at the gene level . Affinity isolation of receptor proteins from all seven strains with biotinylated bovine transferrin identified a 100-kilodalton iron-regulated outer membrane protein as the bovine transferrin receptor . Iron-regulated outer membrane proteins of 71 and 77 kilodaltons were isolated along with the 100-kilodalton protein when less stringent washing procedures were employed in the affinity isolation procedure.

Avian Dis, 1990 Jul-Sep, 34(3), 539 - 47
Comparison of enzyme-linked immunosorbent assay with dot immunobinding assay for detection of antibodies against Pasteurella multocida in turkeys; Choi KH et al.; A dot immunobinding assay (DIA) was developed to detect antibodies against Pasteurella multocida in turkey serum . Five coating antigens, namely, whole-cell (WC) antigen, sonicated cell lysate (SCL), crude capsular extract (CE), formalin extract (FE), and heat-stable antigen (HSA), were compared by enzyme-linked immunosorbent assay (ELISA) and DIA using reference antisera against P . multocida organisms . WC and SCL antigens showed higher sensitivity, whereas FE and HSA antigens were more specific coating antigens in both assays . The specificity of DIA was greater than ELISA by comparing the P/N ratios of HSA against serum prepared from heterologous serotype of P . multocida . The DIA had also several distinct advantages over the ELISA, which included reduction of the manipulation time and more uniform binding of coating antigens onto the nitrocellulose membranes compared with binding of coating antigens to microtiter plates for ELISA.

Kansenshogaku Zasshi, 1990 Jul, 64(7), 866 - 70
{A case of Pasteurella multocida infection in bronchiectasis}; Hiura K et al.; Pasteurella multocide (P . multocida), a small gram-negative bacillus, has been known to be the causative agent of hemorrhagic septicemia in animals . P . multocida infection in human was reported as skin abscess and/or septicemia after an animal bit or scratch . Pulmonary infections of P . multocida have been developed in the patients with chronic pulmonary diseases such as bronchiectasis . In Japan, however, P . multocida respiratory tract infections are rare . In this report, a 80-year-old female with bronchiectasis was admitted on August, 1985 . She had a productive cough, hemosputum, and a low grade fever . The chest X-P on admission showed an atelectasis of the left middle lobe and severe bronchiectatic changes of the left lower lobe . P . multocida was isolated from her sputa . The chemotherapy of CTM resulted in clinical improvement . On May 1988, she complained of a productive cough and a low grade fever again . P . multocida was isolated from the sputum on several occasions in significant numbers (1 x 10(8)/ml) . Recently, the cases of the chronic respiratory diseases have been increasing . We think, P . multocida is important and should be considered as a pathogen in the care of chronic pulmonary diseases.

Vet Microbiol, 1990 Jul, 24(1), 55 - 62
Bactericidal activity in the sera of mice vaccinated with Pasteurella multocida type A; Wijewardana TG et al.; The susceptibility of Pasteurella multocida to killing by serum and the ability of protective vaccines to stimulate this mechanism of immunity in mice were investigated . P . multocida type of bovine origin was used to prepare a vaccine incorporating heat killed organisms and for homologous infection of mice . Bactericidal capacity and ELISA antibody titres were determined for individual mouse sera . Protection was clearly associated with bactericidal antibodies raised by vaccination . The bactericidal assay may be useful as a rapid, simple screening test of vaccinated mice for functional protective antibody levels.

J Emerg Med, 1990 Jul-Aug, 8(4), 437 - 40
A case of unexpected pasteurella multocida bacteremia; Ernst AA et al.; A case of Pasteurella multocida bacteremia in a previously healthy hospital employee is presented . The patient had sustained a scratch from his dog four days prior to being seen in the emergency department with adequate healing and no evidence of localized infection . He presented with an acute febrile illness, and was discharged from the emergency department with a diagnosis of viral syndrome . He was asked to return to the hospital the next day when a bacteriology report of gram negative rods in both aerobic and anaerobic blood culture bottles was received in the emergency department . Pasteurella multocida bacteremia/septicemia is seen most frequently in immunocompromised patients but the diagnosis should be considered in any patient with a febrile illness and exposure to cats or dogs.

Res Vet Sci, 1990 Jul, 49(1), 117 - 9
Autoagglutination and the specificity of the indirect fluorescent antibody test applied to the identification of Taylorella equigenitalis; Ter Laak EA et al.; Because the first strains of Taylorella equigenitalis isolated in the Netherlands autoagglutinated, identification was difficult . The source of carbon dioxide to create a carbon dioxide atmosphere for incubation influenced the emulsifiability of these strains . Strains were emulsifiable when cultivated in a carbon dioxide incubator (7 per cent carbon dioxide in air), but were autoagglutinable when cultivated in a candle jar, or in a jar with a carbon dioxide system or anaerobic system without the palladium catalyst . When strains autoagglutinated, they were identified by the indirect fluorescent antibody test . Although strains of other bacterial species, in particular Pasteurella haemolytica, also showed fluorescence, which was partly caused by autofluorescence, the indirect fluorescent antibody test appeared to be a reliable additional test for identifying T equigenitalis.

Zentralbl Veterinarmed B, 1990 Jul, 37(5), 369 - 76
Serological surveillance for antibodies against different avian infectious agents on turkey flocks naturally infected with turkey rhinotracheitis; Hafez HM; Turkey Rhinotracheitis (TRT) in the state of Baden-Wurttemberg, Germany appears to have become endemic affecting all farms and every new restocking . In 5 meat turkey flocks, serological surveillance for antibodies to TRT-, IB- and IBD-viruses, as well as to Pasteurella multocida were carried out using ELISA tests . Furthermore, sera were examined for the presence of antibodies to avian adenovirus (CELO virus), reo- and paramyxo-viruses 1 and 3 . The birds were bled at 4 week intervals starting at the first day of age through the 20th week . Serological data indicated that in all turkey flocks surveyed after natural exposure to infection, there was a significant increase to TRT antibody levels which was usually accompanied with an increase in the number of positive sera to adenovirus . In addition, no antibodies to IB- and IBD-viruses as well as to Pasteurella multocida could be detected in any of the examined sera . The results related to reo- and paramyxo-viruses 1 and 3 will also be discussed.

Vet Microbiol, 1990 Jul, 24(1), 81 - 8
The influence of growth conditions of Pasteurella multocida on its ability to colonise the nasal mucosa of SPF piglets; Elias B et al.; Colonisation of type D Pasteurella multocida was studied in five groups of seven SPF piglets each . Piglets of Group 1 were kept together with seven 5-week-old piglets obtained from a large herd infected with toxigenic P . multocida for 16 weeks (contact infection) . These piglets were made free from toxigenic Bordetella bronchiseptica by local immunisation . Piglets of Group 2 were inoculated with 5 x 10(7) colony-forming units (cfu) of P . multocida washed from the nasal mucosa of piglets free from toxigenic B . bronchiseptica with fetal calf serum . Piglets of Group 3 were inoculated intranasally with 5 x 10(7) cfu of P . multocida washed from yeast-extract proteose-peptone cystine (YPC)-blood agar with fetal calf serum . Piglets of Group 4 were inoculated with 5 x 10(7) cfu of P . multocida grown in a YPC-based broth without blood . Piglets of Group 5 served as controls . The piglets of Group 1 did not contract P . multocida infection from infected contact piglets . After a single inoculation one of four, while after three inoculations two of three piglets of Group 2 became infected by P . multocida . After a single inoculation none of four, while after three inoculations one of three piglets of Group 3 were colonised by P . multocida . Both single and repeated inoculation failed in piglets of Group 4.

Zentralbl Bakteriol, 1990 Jun, 273(2), 143 - 9
A group of indole-negative bovine strains with high deoxyribonucleic acid homology to Pasteurella multocida; Sachse K et al.; A group of nine bovine Pasteurella strains not producing indole were investigated for their taxonomic relationships with Pasteurella multocida, Pasteurella haemolytica and Pasteurella canis . For all strains, DNA-DNA hybridization has revealed a high genetic relatedness at the species level to P . multocida and significantly lower homologies of only 18-41% towards P . haemolytica and 11-15% towards P . canis . Guanine plus cytosine values of 38.0 to 42.1 mol% and several phenotypic characters have been found to be different from the established pattern for P . multocida subspecies . It is suggested that the strains represent a new taxon, possibly another P . multocida subspecies.

J Vet Pharmacol Ther, 1990 Jun, 13(2), 192 - 7
Pharmacokinetics of sulfadimidine and its N4-acetyl metabolite in healthy and diseased rabbits infected with Pasteurella multocida; Yuan ZH et al.; The pharmacokinetics of sulfadimidine (SDM) and its N4-acetyl metabolite (N4SDM) were investigated after intravenous bolus injection of a single dose (200 mg/kg) of SDM in normal and diseased New Zealand white rabbits . The apparent distribution volume at steady state, total body clearance and elimination half-life of SDM in normal animals were 0.7 +/- 0.3 l/kg, 0.57 +/- 0.24 l/kg/h and 1.6 +/- 1.3 h, respectively . Of the administered dose, 62.1% was metabolized by N4-acetylation, and 12.7 +/- 1.1 and 2.8 +/- 1.8% of the dose was excreted as free drug by the kidney and gastrointestinal tract, respectively . The 'apparent' formation and elimination half-lives of N4SDM were 0.6 +/- 0.4 and 2.2 +/- 1.1 h, respectively . The metabolite was eliminated mainly by excretion through the kidney . There was no significant effect of acute pasteurellosis on the pharmacokinetics of either SDM or N4SDM in rabbits.

J Clin Microbiol, 1990 Jun, 28(6), 1438 - 40
Selective medium for Pasteurella multocida and its use to detect oropharyngeal carriage in pig breeders; Avril JL et al.; A selective culture medium for isolation of Pasteurella multocida was prepared by incorporating 2 mg of amikacin per liter, 4 mg of vancomycin per liter, and 4 mg of amphotericin B per liter into Mueller-Hinton blood agar . Use of this medium revealed the presence of P . multocida in the oropharynges of 19 of the 49 pig breeders who were examined.

Infect Immun, 1990 Jun, 58(6), 1671 - 7
Bovine pulmonary endothelial cell damage mediated by Pasteurella haemolytica pathogenic factors; Breider MA et al.; The in vitro effects of Pasteurella haemolytica components on bovine pulmonary endothelial monolayers were investigated to determine the relative role of individual bacterial factors in the pathogenesis of bovine pulmonary pasteurellosis . Bovine pulmonary endothelial monolayers were treated with P . haemolytica bacterial culture supernatant (CS) and P . haemolytica lipopolysaccharide . At 22 h postinoculation, the CS produced severe damage to the endothelial cells, indicated by high 51Cr release, extensive cellular detachment, and morphologic changes characterized by cell contraction, cytoplasmic blebbing, and loss of monolayer confluency . The neutralization of leukotoxin activity of the CS by heat inactivation was ineffective in decreasing the damage to endothelial cells; however, leukotoxin-neutralizing monoclonal antibody slightly diminished the toxic effect . P . haemolytica lipopolysaccharide by itself or as a supplement to CS produced endothelial cell damage similar to that of CS . The preincubation of CS dilutions (10(-1) and 10(-2)) or P . haemolytica lipopolysaccharide with polymyxin B almost completely eliminated cell toxicity . These studies show that P . haemolytica produces a soluble factor that is consistent with bacterial lipopolysaccharide and that is directly toxic to bovine pulmonary endothelial cells in vitro.

J Clin Microbiol, 1990 Jun, 28(6), 1151 - 8
Specificity of bovine serum antibody to capsular carbohydrate antigens from Pasteurella haemolytica; McVey DS et al.; A more complete understanding of the bovine immune response to antigens of Pasteurella haemolytica biotype A, serotype 1, will improve control of bovine respiratory disease (BRD) . Sera were obtained from blood samples of calves as they transited the market system of eastern Tennessee and were transported to a feedlot in Texas . The clinical histories and performance data were recorded and compared with serologic findings . The calves underwent a natural challenge of BRD . Serologic and bacteriologic evaluation indicated that P . haemolytica A1 was a significant component of the challenge . Serum antibody titers against P . haemolytica A1 capsular antigens (in enzyme-linked immunosorbent assay and hemolysin-in-gel test) increased by day 15 and continued at high levels through day 56 . The animals that remained free of BRD had higher initial serum antibody concentrations than those that succumbed to BRD . The specificity of the immunoglobulin G subclass 1 (IgG1) anticapsular antibody to P . haemolytica A1 increased from day 8 to day 29 as evidenced by a decrease in P . haemolytica A2 absorption inhibition from 60% (day 8) to 15% (day 29) . However, IgA, IgG2, and IgM were more serotype specific on both days 8 and 29 . There were no significant changes in anti-P . haemolytica A2 antibody titers . Both in vitro complement-dependent bacteriolysis and C3 deposition on the surface of the bacteria increased significantly (P less than 0.01) in a serotype-specific fashion from day 8 to day 29 . These calves showed a humoral immune response to capsular polysaccharide antigens of P . haemolytica A1 . Such a response may be an important component of immunity to BRD.

Can J Vet Res, 1990 Jun, 54(3), 337 - 42
A group level analysis of the associations between antibodies to seven putative pathogens and respiratory disease and weight gain in Ontario feedlot calves; Martin SW et al.; The associations, at the group level, between serological titer to Pasteurella haemolytica surface antigens (Ph), Pasteurella haemolytica cytotoxin (Ph-cytox), infectious bovine rhinotracheitis virus (IBRV), bovine virus diarrhea virus (BVDV), parainfluenza-3 virus (PIV3), respiratory syncytial virus (RSV), Mycoplasma dispar (Md), M . bovis (Mb), and respiratory disease treatment rates, relapse rates, and 28 day weight gains were investigated in 14 groups of calves entering two feedlots during years 1983-1985, in Ontario . Based on least squares regression analyses, seroconversion rates to Mb and BVDV were predictive of increased respiratory disease rates, and seroconversion rates to Ph, Ph-cytox, Md and PIV3 were predictive of decreased weight gains . The R2 for predicting weight gains was much higher than for morbidity rates (0.75 vs 0.47 respectively) . Titer data were not predictive of relapse rates . Group level analyses were performed because calves are managed as groups (e.g . pens) in commercial feedlots . Only BVDV seroconversion rates were related to increased risk of respiratory disease at both the individual and group levels of organization . Mycoplasma may be important factors in causing respiratory disease, and their relationship to potentiating the effects of other respiratory pathogens needs further investigation.

Zentralbl Veterinarmed B, 1990 Jun, 37(4), 297 - 308
Pulmonary lesions induced by a Pasteurella haemolytica cytotoxin preparation in calves; van den Ingh TS et al.; Intrabronchial instillation of a Pasteurella haemolytica type A1 crude cytotoxin preparation in calves resulted in pulmonary gross and microscopic lesions comparable to spontaneous and experimental pasteurellosis . In the acute stage of the lesion electronmicroscopy revealed intravascular accumulation, degeneration and fragmentation of leukocytes in the interalveolar septa . Secondary thrombus formation and increased vascular permeability resulted in alveolar flooding, fibrin deposition, extravasation of erythrocytes and loss of alveolar epithelium . No cytotoxicity was observed for the tracheal (in vitro) and bronchial epithelium (in vivo) . The pathogenesis of the vascular lesions and their significance for the development of the typical lesions of pneumonic pasteurellosis is discussed.

Vet Rec, 1990 May 5, 126(18), 452 - 6
Detection and distribution of toxigenic Pasteurella multocida in pig herds with different degrees of atrophic rhinitis; Goodwin RF et al.; Four herds of pigs were selected which had different degrees of clinical atrophic rhinitis and used different specific counter-measures . In two of them, the clinical signs occurred spasmodically and were slight . The sows, suckling pigs and growing pigs in all the herds were sampled for toxigenic Pasteurella multocida . In one of the slightly affected herds (herd D), the weaners were moved to a second farm for finishing . No toxigenic P multocida were found at the breeding farm, but 50 per cent of the large growing pigs were positive . It seemed that the organism had entered only at the finishing farm and that the mild clinical signs were due to the infection starting in older pigs than usual . In the second mildly affected herd, 47 per cent of the sows and 42 per cent of the growers were infected . Three toxigenic isolates from this herd produced as severe turbinate damage experimentally in specific-pathogen-free pigs as a stock pathogenic strain . Except in herd D, toxigenic P multocida were found in all the age groups of pigs sampled . However, the pattern of distribution of the organism within the herds was not obviously correlated with the severity of the disease . In a fifth herd there were obvious cases of clinical atrophic rhinitis, with marked turbinate atrophy, from which toxi-genic P multocida were recovered in abundance . Subsequently, the clinical disease disappeared and, despite extensive and repeated sampling, the organism was not found again.

Dtsch Tierarztl Wochenschr, 1990 May, 97(5), 195 - 6
{Atrophic rhinitis of swine: neutralization of the toxin of Pasteurella multocida}; Schimmelpfennig H; The neutralization of the lethal as well as the growth-retarding action of the toxin on mice by an antitoxic serum is described.

Vet Microbiol, 1990 May, 22(4), 309 - 17
A colourimetric, microplate assay for the leucotoxin of Pasteurella haemolytica; Craig FF et al.; Culture supernates of Pasteurella haemolytica, which contain leucotoxin, inhibited the reduction of nitroblue tetrazolium (NBT) by bovine and ovine but not rabbit leucocytes in response to phorbol 12-myristate 13-acetate (PMA) . Culture supernates of P . multocida, which contain no leucotoxin, had no inhibitory effect on the response of leucocytes from any species . The inhibition of NBT reduction was assessed visually or spectrophotometrically in the wells of microplates and used as a simple assay for leucotoxin . It was as sensitive as the trypan blue dye-exclusion method and did not require the use of radioisotopes . In addition, sera from P . haemolytica-infected calves inhibited leucotoxin activity in the microplate assay . Thus, inhibition of NBT reduction after stimulation of ruminant leucocytes with PMA can be used as a simple, specific assay for leucotoxin and for anti-leucotoxin antibodies.

Res Vet Sci, 1990 May, 48(3), 344 - 9
Immune defence mechanism against blood-borne Pasteurella multocida in turkeys; Tsuji M et al.; Humoral and cellular immune defence factors involved in controlling blood-borne Pasteurella multocida were investigated in turkeys by the passive transfer of immune serum or by the treatment with macrophage-activating agents . The treated and untreated birds were intravenously inoculated with a virulent strain of P multocida, and the viable bacteria in the blood, liver and spleen were counted . In untreated birds, the bacteria were rapidly removed from the blood, and the majority were recovered from the liver and spleen 120 minutes after inoculation . Neither the transfer of immune serum nor the treatment with macrophage-activating agents significantly influenced the clearance rate of bacteria from the blood . The number of bacteria recovered from the liver 120 minutes after inoculation was slightly lower in the birds treated with macrophage-activating agents and significantly lower in those given immune serum than in the untreated birds . None of the treatments, however, significantly changed the number of bacteria recovered from the spleen 120 minutes after inoculation . The results suggest that the phagocytes in the liver, but not in the spleen, play a crucial role in the intravascular defence against P multocida in the presence of specific antibodies.

APMIS, 1990 May, 98(5), 453 - 61
Adherence of Bordetella bronchiseptica and Pasteurella multocida to swine nasal ciliated epithelial cells in vitro; Chung WB et al.; A bacterial adherence assay using swine nasal turbinate fragments was established . Turbinate fragments were incubated with Bordetella bronchiseptica or Pasteurella multocida type D at different concentrations or for different incubation times at 37 degrees C on a shaker at 120 rev/min . B . bronchiseptica phase I strains exhibited strong adherence to swine nasal ciliated epithelial cells . The number of adherent bacteria per cell increased when the bacterial concentration or incubation time increased (0, 15, 30, and 60 min); however, the number of adherent bacteria decreased after 3 or 6 hours' incubation due to the loss of cilia from cells . The optimal bacterial concentration and incubation time were 1 x 10(9) organisms/ml and one hour respectively, which resulted in 7.48 +/- 0.66 (Mean +/- SEM; B . bronchiseptica strain 03) and 9.31 +/- 0.54 (B . bronchiseptica strain 013) adherent bacteria per cell . In contrast to B . bronchiseptica phase I strains, rough phase strains of B . bronchiseptica and all P . multocida strains tested showed no adherence to swine nasal ciliated epithelial cells . All B . bronchiseptica phase I strains could agglutinate calf RBC but rough phase strains could not . Furthermore, pretreatment of B . bronchiseptica phase I organisms with 1 mg/ml or 2 mg/ml of trypsin significantly inhibited the adherence of B . bronchiseptica to ciliated epithelial cells; however, trypsin (2 mg/ml) treatment of bacteria did not decrease their ability to agglutinate calf RBC . From these results we conclude that, in addition to hemagglutinin, other proteinaceous components exist on the surface of virulent B . bronchiseptica that are sensitive to 2 mg/ml trypsin; these are suggested to be the adhesins for the adherence of B . bronchiseptica to swine nasal ciliated epithelial cells.

APMIS, 1990 May, 98(5), 442 - 52
A comparison of different challenge methods for induction of atrophic rhinitis in pigs; Chung WB et al.; Transmission and development of atrophic rhinitis (AR) was studied in 5- to 15-week-old pigs (Groups 2-7) originating from a herd free of AR, and compared to unexposed healthy pigs (Group 1), and pigs from a herd with endemic AR (Group 8) . At the start of the trial, pigs in Groups 2-5 were challenged intranasally twice a week for 3 weeks with pure cultures of bacteria originating from the endemic AR herd: Nontoxigenic Pasteurella multocida type A (PmA) plus Bordetella bronchiseptica phase I (Bb) (Group 2); PmA + toxigenic Pm type D (PmD) (Group 3); PmD only (Group 4); and PmD + Bb (Group 5) . Group 6 pigs were challenged with nasal wash of pigs from the endemic AR herd, and Group 7 pigs were challenged by being housed together in the same pen with Group 8 pigs throughout the study . Nasal swabs of all pigs were cultured 5 times during the study . Serum was collected at 6 weeks post challenge . Average daily gain (ADG) and turbinate lesions (turbinate gross lesions by visual scoring and by Turbinate Perimeter Ratio, TPR, scoring, and histopathological lesions) were measured at the time of slaughter at 15 weeks of age . Mean TPR value for the Group 1 pigs was 1.64, which was significantly (P less than 0.05) different from the mean TPR value of 0.58 for the pigs from the endemic AR herd (Group 8), the 0.79 value for Group 6 pigs, and 1.03 value for Group 7 pigs . Of pigs challenged with pure bacterial cultures, only Group 5 (PmD + Bb) developed significant AR (mean TPR = 1.24) . Only one pig in each of Groups 2 and 3, and two pigs in Group 4 showed TPR values indicative of AR (TPR less than 1.30) . However, histopathological examination showed that those pigs were recovering from the infection 7 weeks post challenge . Constant exposure to certain bacteria or other factors in nasal washings, stress of crowding or poor environmental conditions might be required to experimentally produce AR in 5-week and older pigs similar to that in naturally infected pigs . There was no relationship between turbinate lesions and the isolation frequency or quantity of PmA, PmD, or Bb . Antibody levels against PmA or PmD had moderate to high correlation with TPR values (r = -0.694 and -0.503 respectively) . ELISA values also corresponded well with the type of bacteria inoculated in each group of pigs and appeared to be a sensitive test for PmA, PmD, and Bb infections in pigs.(ABSTRACT TRUNCATED AT 400 WORDS)

J Med Microbiol, 1990 May, 32(1), 55 - 61
Outer membrane proteins of bovine strains of Pasteurella multocida type A and their doubtful role as protective antigens; Abdullahi MZ et al.; Outer membranes were prepared by the Sarkosyl method from 30 strains of Pasteurella multocida and the closely related Taxon 13, which had been isolated from cattle . The patterns of the outer membrane proteins (OMPs) on SDS-PAGE were generally similar to one another, though the four major proteins (a-d) varied somewhat in molecular mass; these patterns allowed the strains to be arranged into 12 groups . Taxon 13 strains and typical P . multocida strains were indistinguishable, both types being found within the same group . Mice were vaccinated with heat-killed bacteria of three strains and challenged with 10 LD50 of homologous and heterologous live bacteria, representing groups based on OMP patterns; the best protection was afforded by strain W674, which protected against nine of the 17 challenge strains; but there was no correlation between protection and PAGE pattern . Pre-vaccination and pre-challenge sera were used in immunoblotting to probe OMPs from protective and non-protective strains . All three vaccines produced antibody to proteins a and d; these proteins appeared to be common to all strains, varying in molecular mass but not in overall antigenic expression . The antibody response to the other two major OMPs appeared to be PAGE-group specific . There was no correlation between protection and the antigen pattern seen by immunoblotting.

Infect Immun, 1990 May, 58(5), 1485 - 7
Influence of Pasteurella haemolytica A1 crude leukotoxin on bovine neutrophil chemiluminescence; Czuprynski CJ et al.; Pasteurella haemolytica A1 crude leukotoxin (25%, vol/vol) rapidly diminished the bovine neutrophil chemiluminescence response to opsonized zymosan . This inhibition was neither prevented nor reversed by 75 mM sucrose . Dilute leukotoxin did not directly stimulate neutrophil chemiluminescence nor did it alter the chemiluminescence response of the neutrophils to opsonized zymosan.

Mol Microbiol, 1990 May, 4(5), 821 - 30
The complete nucleotide sequence of the Pasteurella multocida toxin gene and evidence for a transcriptional repressor, TxaR; Petersen SK; The osteolytic toxin of Pasteurella multocida induces bone resorption in vivo and in vitro (Foged et al., 1988; Kimman et al., 1987) . In this report the toxin-encoding toxA gene is sequenced, and the deduced primary structure of the toxin shows a protein of 1285 amino acids, containing a striking homology to a metal-binding motif . Evidence that expression of the toxA gene is repressed at a transcriptional level in Escherichia coli is presented . Repression could be abolished either by deletion of a region upstream of toxA, or by a putative frame-shift mutation in the same region . The repressor protein encoded within this region was efficient in trans, and was named TxaR.

Rev Infect Dis, 1990 May-Jun, 12(3), 440 - 8
Pasteurella multocida meningitis in an adult: case report and review; Kumar A et al.; Pasteurella multocida is a rare cause of adult meningitis . Close animal contact prior to onset of illness is frequent and represents the usual mode of introduction of the organism . In reports of a total of 21 cases of P . multocida meningitis in adults (this case report and 20 described previously in the English-language literature), 18 researchers commented on the occurrence of animal contact: two cases (11%) involved cat bite, 13 (72%) involved animal contact without bite, and three (17%) occurred in the absence of recognized animal contact . Clinical presentation was typical of bacterial meningitides . Overall mortality rate was 30% . The best predictors of poor outcome were initial hemodynamic instability and age greater than 60 years . Documented bacteremia (40% of cases) was not predictive of higher mortality . Effective therapy is based on early recognition of the possibility of P . multocida meningitis and prompt initiation of treatment with penicillin, ampicillin, or a third-generation cephalosporin.

Vet Pathol, 1990 May, 27(3), 150 - 61
Immunohistochemical localization of Pasteurella haemolytica A1-derived endotoxin, leukotoxin, and capsular polysaccharide in experimental bovine Pasteurella pneumonia; Whiteley LO et al.; Six, 5- to 10-week-old male Holstein calves were inoculated intratracheally with 5 x 10(9) logarithmic growth phase Pasteurella haemolytica biotype A serotype 1 (A1) . Immunohistochemical techniques in conjunction with the use of monoclonal antibodies directed against P . haemolytica A1-derived lipopolysaccharide (LPS), capsular polysaccharide, and a polyclonal rabbit anti-leukotoxin antibody were used to localize their respective antigens in tissue sections of pneumonic lung at the light and electron microscopic levels . We found the following: 1) LPS, capsular polysaccharide, and leukotoxin were released into the inflammatory exudate; 2) LPS was found within the cytoplasm of neutrophils (located in the alveolus and alveolar wall), alveolar macrophages, endothelial cells, pulmonary intravascular macrophages, and on epithelial cell surfaces; 3) capsular polysaccharide was found in the alveolus and alveolar macrophages but not in cells of the alveolar wall; and 4) leukotoxin was associated with cell membranes of degenerating inflammatory cells located in the alveolus . This is the first study that demonstrates the presence of leukotoxin in the pulmonary inflammatory lesions caused by P . haemolytica A1 and implicates endotoxin as an important factor in the genesis of the pulmonary lesions.

J Bacteriol, 1990 May, 172(5), 2343 - 50
Secretion and expression of the Pasteurella haemolytica Leukotoxin; Highlander SK et al.; The Pasteurella haemolytica leukotoxin gene cluster (lktCABD) is homologous to the Escherichia coli hemolysin locus (hlyCABD) . Since the cloned leukotoxin (LktA) is not secreted from E . coli cells, a heteroplasmid complementation system was developed that permits secretion of the leukotoxin from cells expressing the hemolysin transport proteins HlyB and HlyD . We observed that the secreted leukotoxin protein had weak hemolytic activity when activated by either the HlyC or LktC proteins and that LktC expressed in E . coli could confer weak hemolytic activity upon hemolysin . Thus, it appears that the accessory proteins of the leukotoxin and hemolysin gene clusters are functionally similar, although their expression in E . coli is not equivalent . Northern (RNA) blot analysis of the P . haemolytica leukotoxin gene cluster revealed a major 3.5-kilobase transcript that includes the lktC and lktA genes . The start site for this transcript mapped to a cytosine residue 30 nucleotides upstream from the putative start of lktC; a similar initiation site was observed in E . coli, although adjacent cytosine and adenine residues were also utilized . The 3.5-kilobase transcript terminated near the rho-independent terminator structure between lktA and lktB, but transcription may continue, via antitermination or de novo transcription initiation, into the downstream lktB and lktD genes . We propose that the lack of LktB and LktD function in E . coli is a result, at least in part, of poor lktBD transcription and suggest that a P . haemolytica-specific regulator is required for optimal expression of the leukotoxin genes.

Lab Anim Sci, 1990 May, 40(3), 289 - 92
Naturally acquired Pasteurella multocida infection in rabbits: immunological aspects; DiGiacomo RF et al.; Natural infection with P . multocida in New Zealand White rabbits was followed in 2 to 3 weeks by development of immunoglobulin (Ig)M and IgG serum antibodies . The IgM response peaked and returned to lower levels within several weeks after infection, whereas the IgG response progressively increased and remained elevated.

Res Vet Sci, 1990 May, 48(3), 383 - 5
Distribution of Pasteurella haemolytica in the respiratory tracts of carrier calves and those subsequently infected experimentally with Dictyocaulus viviparus; Shoo MK et al.; Distribution of Pasteurella haemolytica in the respiratory tracts of calves with no apparent clinical signs of illness and those infected experimentally with Dictyocaulus viviparus was determined so as to define carrier sites for this organism . The calves had been positive by nasopharyngeal swab for either P haemolytica A2 or A1 for at least two months or for over a month, respectively, before slaughter . P haemolytica A1 was acquired following horizontal spread from other infected calves . It was observed post mortem that P haemolytica A1 or A2 resided in the tonsils and retropharyngeal lymph nodes of calves of both groups . In addition to these sites, P haemolytica A1 was also isolated from the right cranial lung lobe of one of the calves from the D viviparus infected group although there was no evidence of pasteurella associated pneumonia . It was concluded that tonsil and retropharyngeal lymph nodes appear to be the most important carrier sites for P haemolytica when compared to other tissues of the bovine respiratory tract.

Zentralbl Veterinarmed A, 1990 May, 37(4), 253 - 8
Plasma disposition and tolerance of aditoprim in horses after single intravenous injection; von Fellenberg RL et al.; Aditoprim, a broad spectrum antimicrobial agent acting as a reversible dihydrofolate reductase inhibitor, was intravenously injected into four 12 to 24-year old horses at a dosage of 5 mg/kg b . w . Blood samples were collected over a 48-hour period after drug injection, and the separated plasma samples were assayed for aditoprim by high performance liquid chromatography . The body temperature, heart rate, respiration rate, and behaviour were recorded during the experiment . The bilirubin and urea concentrations were also determined in several plasma samples, and liver function tests were carried out . The concentrations of aditoprim in the plasma of horses were higher than the MIC of this drug against recently isolated pathogens for 6-13 h (Pasteurella haemolytica A 1) to 48 h (E . coli) . The main pharmacokinetic characteristics of aditoprim in horses were: a large volume of distribution, reaching a mean value of 7.8 l/kg; a mean plasma clearance of 5.0 l/min; a plasma elimination half-life of 12 h . The clinical observations, blood chemistry, and liver function tests all demonstrated that the drug was well tolerated by the horses, although it was injected intravenously as a 25% solution . It was concluded that the 25% aditoprim injection solution could be used in horses without adverse effects at 5 mg/kg . Furthermore, aditoprim should demonstrate good antibacterial effects in horses when intravenously injected once a day.

Vet Rec, 1990 Apr 28, 126(17), 434 - 7
Atypical Pasteurella strains producing a toxin similar to the dermonecrotic toxin of Pasteurella multocida subspecies multocida; Kamp EM et al.; This paper is the first report of the production of a dermonecrotic toxin by pasteurella strains that do not belong to the species Pasteurella multocida subspecies multocida . Four strains, isolated from cattle with atrophic rhinitis, were characterised phenotypically . The strains were related to pasteurellaceae, but their taxonomic position remained unclear . The strains produced a toxin that caused a haemorrhagic dermonecrosis in guinea pigs and was lethal to mice . Both effects were neutralised by an antiserum against the purified dermonecrotic toxin of P multocida subspecies multocida . Western blot analysis of culture filtrates of the bovine strains revealed a protein, with the same molecular weight as dermonecrotic toxin, which reacted with both polyclonal and monoclonal antibodies against the toxin . In an immunodiffusion test, anti-dermonecrotic toxin serum did not discriminate between the toxin of the bovine strains and the toxin of P multocida subspecies multocida . It is concluded that these atypical pasteurella strains produce a toxin that is closely related to the dermonecrotic toxin of P multocida subspecies multocida.

Vet Rec, 1990 Apr 21, 126(16), 376 - 8
Suspected adverse reactions to medicines during 1989; Gray A et al.; There was an increase in reports of suspected adverse reactions to veterinary medicines in 1989 with 329 reports (compared with 206 in 1988), from veterinary surgeons, farmers and the public, comments the Veterinary Medicines Directorate (VMD) . Suspected adverse reactions to clostridial/pasteurella vaccines in sheep were a dominant feature and important experience was gained both in terms of liaison with the farming press, and in handling large scale incidents involving PML products . The general trend towards increased reporting of adverse drug effects continues . The UK is the only EC member state to have a PML system and the VMD is looking with some urgency at ways of ensuring the more representative reporting of all categories of drug . Substantial liaison with the veterinary pharmaceutical industry occurred during the year and 204 product reports were requested from companies.

Tijdschr Diergeneeskd, 1990 Apr 15, 115(8), 354 - 6
{Pasteurella haemolytica serotyping}; Visser IJ et al.; Forty-nine strains of Pasteurella haemolytica were serotyped in a pilot study . The majority of strains were isolated from sheep which had died from fibrinous pneumonia and small numbers from cases of sepsis, polyserositis, mastitis and meningitis . Serotype A2 was found to be the most prevalent: 69.4 per cent . In addition, serotype A7 with 18.4 per cent and serotypes A1 and A6, both 6.1 per cent, were identified . Biotype T strains were not detected in this study . Further research is required into the seasonal prevalence of P . haemolytica serotypes in sheep and cattle . This knowledge may help to improve herd health schemes for sheep and cattle in the Netherlands.

Avian Dis, 1990 Apr-Jun, 34(2), 491 - 4
Dermal necrosis caused by Pasteurella multocida infection in turkeys; Glass SE et al.; Severe dermal necrosis caused by Pasteurella multocida Serotype 1 was diagnosed in three dressed turkey carcasses and two live turkeys from a commercial flock . The dressed carcasses were among several condemned at a processing plant . The isolate, P . multocida Serotype 1, produced progressive dermal necrosis when experimentally inoculated into injured skin of turkeys . The organism was reisolated from the dermal lesions . The turkey houses were found to be infested by mice; the skin injury and infection with P . multocida probably originated from mouse bites.

Avian Dis, 1990 Apr-Jun, 34(2), 419 - 24
Differentiation of field isolates of Pasteurella multocida serotype 3,4 from live vaccine strain by genotypic characterization; Snipes KP et al.; Fifty-five serotype 3,4 isolates of Pasteurella multocida, isolated from turkeys dead from fowl cholera, were characterized (fingerprinted) genotypically for comparison with the serotype 3,4 live fowl cholera vaccine principally used in turkeys in California . Twenty-three isolates were obtained from turkeys vaccinated with the M9 live vaccine, and 32 additional isolates were from turkeys not vaccinated for fowl cholera . Methods of characterization included restriction endonuclease analysis of chromosomal DNA and ribotyping, a technique for highlighting restriction site heterogeneity of highly conserved ribosomal RNA genes and associated sequences using a radiolabeled rRNA probe . Eight different genotypes or ribotypes were detected in these isolates by the above methods . Of 23 isolates from M9-vaccinated turkeys flocks, 19 were the same ribotype as M9 . Thirty of 32 isolates recovered from unvaccinated turkeys were different ribotypes from M9 . The remaining two isolates resembled M9 and were recovered from two different flocks placed in succession on a turkey farm where a flock placed previously had been vaccinated with M9, suggesting interflock transmission . Ribotyping and restriction endonuclease analysis appear to be useful tools to aid in the determination of the role that the live vaccine plays in fowl cholera epidemiology.

Avian Dis, 1990 Apr-Jun, 34(2), 384 - 8
Virulence and toxigenicity of capsular serogroup D Pasteurella multocida strains isolated from avian hosts; Rhoades KR et al.; Five capsular serogroup D strains of Pasteurella multocida isolated from avian hosts were examined for virulence and toxigenicity . Virulence was based on development of lethal infections or lesions following intramuscular exposure of turkey poults . The four strains isolated from turkeys varied from slightly to moderately virulent; the strain isolated from a chicken was avirulent . Poults exposed by intra-airsac inoculation with relatively few organisms of the more virulent of the strains had a high mortality rate; however, intranasal exposure of poults with this strain did not cause clinical disease or establish infections . All strains from turkeys were toxigenic, producing heat-labile toxins that killed poults when administered intraperitoneally and caused focal dermal lesions when administered intradermally . Using these criteria, the strain from a chicken was not toxigenic . The demonstration of virulence, particularly the high mortality in poults exposed via air sacs, indicates avian capsular serogroup D strains are a potential cause of fowl cholera.

Avian Dis, 1990 Apr-Jun, 34(2), 381 - 3
Pasteurella multocida colonization and invasion in experimentally exposed turkey poults; Rhoades KR et al.; Turkey poults were examined microbiologically to detect colonization and invasion following exposure to selected strains of Pasteurella multocida . A variety of host tissues was examined 24 hours or less after exposure via the upper respiratory tract . Recovery of P . multocida from the dorsal pharynx was used as an indicator of colonization; recovery from selected internal organs was used as an indicator of invasion . The frequency of colonization and invasion by capsulated and uncapsulated forms of an avirulent live-vaccine strain was low . A virulent strain readily colonized and invaded . Colonization occurred in less than 6 hours after exposure, and invasion occurred between 6 and 12 hours after exposure.

Avian Dis, 1990 Apr-Jun, 34(2), 260 - 6
The pathogenesis of Pasteurella multocida serotype A:3,4 infection in turkeys: a comparison of two vaccine strains and a field isolate; Prantner MM et al.; The pathogenesis of avian pasteurellosis caused by two vaccine strains, M-9 and Clemson University (CU), and a highly virulent field isolate, 86-1913, of Pasteurella multocida (serotype A:3,4) was studied in 7-week-old turkeys inoculated by an oculo-nasal-oral technique . Turkeys inoculated with strain CU and isolate 86-1913 developed severe progressive bacteremia that began at 4 hours postinoculation (PI) and peaked at 16-20 hours PI . Turkeys inoculated with strain CU and isolate 86-1913 had significantly higher concentrations of bacteria in blood and tissues, and greater histologic lesion scores for necrosis, heterophil infiltrates, and intralesional bacteria than turkeys inoculated with strain M-9 . Immunohistochemical staining specific for P . multocida demonstrated numerous extracellular bacteria in tissues from turkeys inoculated with strain CU and isolate 86-1913 . The mortality for turkeys inoculated with isolate 86-1913 was significantly higher than for turkeys receiving the two vaccine strains.

Can J Vet Res, 1990 Apr, 54(2), 238 - 43
A model for the induction of Pasteurella multocida type-A pneumonia in pigs; Hall WF et al.; A model for the induction of pneumonia caused by Pasteurella multocida type-A was developed . Anesthetized pigs were dosed intratracheally with 10(10) colony forming units of P . multocida type-A suspended in a total dose of saline based on the pig's body weight (8 mL/kg) . A severe bronchopneumonia was present when the treated pigs were euthanized seven days postinfection . The mean percentage of pneumonic lesions in the treated pigs, as determined by morphometric measurement, was 14.03 +/- 7.01 (X +/- SD) . In contrast, in the control pigs, the mean percentage of pneumonic lesions was 0.59 +/- 0.52 . For the treated pigs during the period following induction of pneumonia, weight gain and feed intake were reduced significantly (p less than 0.05) compared to the controls . It was shown that severe pneumonia could be induced without the use of other infectious agents, which could potentially confound the experimental model.

Can J Vet Res, 1990 Apr, 54(2), 232 - 7
Effects of Pasteurella haemolytica A1 culture supernatant on mechanisms controlling bovine alveolar macrophage oxygen radical production; Conlon PD et al.; Pasteurella haemolytica A1 culture supernatant containing leukotoxin, and modifiers of cyclic nucleotide and arachidonate metabolism, were evaluated for their ability to alter oxygen radical production by pulmonary alveolar macrophages obtained from seven Holstein calves . Calves were sedated, and underwent bronchoalveolar lavage to harvest macrophages, which were then incubated with culture supernatant and/or the drugs and toxins under study, and challenged with opsonized zymosan to induce oxygen radical generation . This was measured by a chemiluminescence technique . Pasteurella haemolytica A1 culture supernatant alone delayed the time to maximum oxygen radical production, although total production was increased . The cyclooxygenase inhibitor indomethacin and the phospholipase inhibitor p-bromophenacyl bromide significantly reduced maximum oxygen radical production, but their effects were diminished in the presence of culture supernatant . Although forskolin markedly inhibited oxygen radical generation, this effect was not altered by culture supernatant . Incubation of macrophages with pertussis toxin had no effect on oxygen radical production, while incubation with cholera toxin did inhibit production . This inhibitory effect was significantly lessened by concurrent incubation with P . haemolytica A1 culture supernatant.

Can J Vet Res, 1990 Apr, 54(2), 227 - 31
Effect of deferoxamine pretreatment on acute pneumonic pasteurellosis and neutrophil oxidative metabolism in calves; Slocombe RF et al.; Iron plays a central role in bacterial infections, influencing both bacterial virulence and host cellular defense mechanisms . We investigated whether iron chelation might be of benefit in the treatment of pneumonic pasteurellosis of calves . Neutrophils obtained from calves previously treated with the iron chelator, deferoxamine, were studied for their responses to latex and opsonized zymosan by luminol-enhanced chemiluminescence and to phorbol myristate acetate and opsonized zymosan by superoxide generation . Treatment with deferoxamine in vivo failed to influence these in vitro measures of neutrophil oxidative metabolism . Furthermore, iron depletion with deferoxamine failed to modify the pathophysiological derangements that occurred in calves following experimental induction of pneumonia by intratracheal inoculation with Pasteurella haemolytica . These data indicate that iron chelation using deferoxamine cannot be recommended as an adjunct to conventional therapy in the treatment of pneumonic pasteurellosis of cattle.

Neth J Med, 1990 Apr, 36(3-4), 207 - 8
Septic monarthritis due to Pasteurella multocida after a cat scratch in a patient with rheumatoid arthritis; Houtman PM; A 60-yr-old woman with a history of seropositive rheumatoid arthritis and using a low dose of corticosteroids presented with a very painful, swollen, red coloured knee with limited range of motion . Physical examination revealed a scratch on her left lower leg without discolouration or induration . Synovial fluid cultures yielded Pasteurella multocida . The pathogenetic significance of this commensal of cats and dogs in man is discussed.

J Wildl Dis, 1990 Apr, 26(2), 283 - 5
Pasteurella multocida infections in rockhopper penguins (Eudyptes chrysocome) from Campbell Island, New Zealand; de Lisle GW et al.; During an investigation into the population decline of rockhopper penguins (Eudyptes chrysocome) on Campbell Island, New Zealand, avian cholera (Pasteurella multocida) was found in dead adults and chicks . An RNA enveloped virus was isolated from Ixodes uriae, a tick which commonly parasitizes rockhopper penguins on the island . It is not known whether this virus is virulent for penguins . No evidence was obtained to suggest that avian cholera was the principal cause for the decline in the rockhopper penguin population.

J Wildl Dis, 1990 Apr, 26(2), 210 - 3
Isolation of Pasteurella haemolytica from tonsillar biopsies of Rocky Mountain bighorn sheep; Dunbar MR et al.; Isolations of Pasteurella haemolytica were compared from tonsillar biopsies versus nasal passages for 29 free-ranging Rocky Mountain bighorn sheep (Ovis canadensis canadensis) from central Idaho . Overall, P . haemolytica was isolated from 11 (38%) of 29 sheep . Two (18%) of the 11 positive samples were from only nasal passages compared to eight (73%) from tonsillar biopsies . Pasteurella haemolytica biotype T was isolated from tonsils of nine sheep and from nasal biopsies . Pasteurella haemolytica biotype T was isolated from tonsils of nine sheep and from nasal passages of only one sheep . Two sheep were positive for P . haemolytica biotype A from nasal passages . Culturing tonsillar biopsies as compared to nasal swab samples was a more reliable technique in detecting P . haemolytica, especially biotype T, in bighorn sheep.

J Wildl Dis, 1990 Apr, 26(2), 204 - 9
Characteristics of Pasteurella multocida isolated from waterfowl and associated avian species in California; Hirsh DC et al.; Characteristics of Pasteurella multocida isolated from tissues of dead waterfowl and associated avian species found at 23 sites located in northern and central California, from January 1986 through January 1988 are reported . Two hundred ninety five isolates of P . multocida were obtained from 23 avian species . Most of the isolates belonged to the subspecies P . multocida multocida (63%), followed by P . multocida gallicida (37%), and by P . multocida septica (less than 1%) . There appeared to be a higher prevalence of P . multocida multocida in Ross' geese (Chen rossi) and Snow geese (Chen coeruleus) . All of the isolates belonged to somatic serotype 1, possessed the A capsule type and were susceptible to the 8 antimicrobial agents tested . None contained plasmid DNA.

Environ Res, 1990 Apr, 51(2), 209 - 17
Effects of sewage sludge on the immune defenses of mallards; Goldberg DR et al.; Sewage sludge contains numerous chemicals that, if ingested, could affect the immunological status of wild birds and, in particular, their resistance to infectious disease . Mallard ducks were fed a diet containing 0, 5, or 20% dried sewage sludge from either Milwaukee or Madison, Wisconsin, for 28 and 57 days, respectively . When subsequently challenged with Pasteurella multocida, the mortality in the sludge-treated groups was no greater than that in the untreated control groups . There was, however, significantly more cadmium (two- to three-fold higher concentration) retained in the livers of birds receiving 20% of either sludge in their feed, as compared to controls.

Int J Syst Bacteriol, 1990 Apr, 40(2), 148 - 53
Actinobacillus rossii sp . nov., Actinobacillus seminis sp . nov., nom . rev., Pasteurella bettii sp . nov., Pasteurella lymphangitidis sp . nov., Pasteurella mairi sp . nov., and Pasteurella trehalosi sp . nov; Sneath PH et al.; Evidence from numerical taxonomic analysis and DNA-DNA hybridization supports the proposal of new species in the genera Actinobacillus and Pasteurella . The following new species are proposed: Actinobacillus rossii sp . nov., from the vaginas of postparturient sows; Actinobacillus seminis sp . nov., nom . rev., associated with epididymitis of sheep; Pasteurella bettii sp . nov., associated with human Bartholin gland abscess and finger infections; Pasteurella lymphangitidis sp . nov . (the BLG group), which causes bovine lymphangitis; Pasteurella mairi sp . nov., which causes abortion in sows; and Pasteurella trehalosi sp . nov., formerly biovar T of Pasteurella haemolytica, which causes septicemia in older lambs.

Avian Dis, 1990 Apr-Jun, 34(2), 315 - 20
Homogeneity of characteristics of Pasteurella multocida isolated from turkeys and wildlife in California, 1985-88; Snipes KP et al.; Five hundred twenty isolates of Pasteurella multocida, collected in California from September 1985 to November 1988, were characterized in the laboratory . Characteristics examined included serotype, capsular type, biotype (subspecies), and possession of plasmid DNA . Three hundred thirty-three isolates recovered from turkeys dying from fowl cholera, 88 isolates from liver turkeys in flocks with fowl cholera outbreaks in the recent past, and 99 isolates from wildlife captured on fowl cholera-outbreak and non-outbreak turkey premises were studied in this manner . Characteristics were fairly homogeneous among isolates, especially those obtained from turkeys . The majority of isolates were serotype 3,4, capsular type A, subspecies multocida, and lacked plasmid DNA . Common serotypes of isolates from turkeys and wildlife sampled on the same premises were noted in eight of 13 cases examined.

Can J Vet Res, 1990 Apr, 54 Suppl, S45 - 7
Molecular aspects of the virulence of Pasteurella multocida; Chanter N; Molecules important to the virulence of all Pasteurella multocida are little known, but much has been learned of isolates causing atrophic rhinitis of pigs . A protein toxin purified from P . multocida or from a recombinant Escherichia coli reproduces atrophic rhinitis and leads to a reduction in weight gain; antitoxin is completely protective . Toxin is important for P . multocida colonization, especially in the presence of the Bordetella bronchiseptica cytotoxin . The P . multocida toxin binds rapidly to embryonic bovine lung cells in vitro leading to an alteration of cell shape without the metabolic and structural changes associated with other toxins . This indicates a novel biochemical mechanism . However, other work suggests a subunit mode of action structurally like hormones and other bacterial toxins.

Can J Vet Res, 1990 Apr, 54 Suppl, S16 - 21
Bacterial adhesion to mucosal surfaces with special reference to Pasteurella multocida isolates from atrophic rhinitis; Pijoan C et al.; Adhesion to mucosal cells is an important virulence attribute of bacterial pathogens colonizing these sites . Bacteria of the upper respiratory system, such as members of the genus Bordetella, have well-defined adhesins . The main adhesin of B . pertussis is the filamentous hemagglutinin which can be used by other bacteria for attachment . The main adhesin of B . bronchiseptica is the bovine erythrocyte hemagglutinin . In both Bordetella species the presence of fimbriae does not appear critical to adhesion . In contrast, atrophic rhinitis (AR)-producing strains of Pasteurella multocida colonize poorly the pig's nasal mucosa . We performed an in vitro trial using newborn pigs' turbinate explants and showed that two toxigenic strains (serotype D fimbria + and serotype A fimbria -) were adherent when observed by scanning electron microscopy (SEM) . Intranasal inoculation of both six week old and newborn SPF pigs with various strains of P . multocida also resulted in colonization . Adhesion was best achieved by toxigenic strains, regardless of possession of fimbria, hemagglutinin or capsular serotype . Colonization was more abundant and constant in tonsils . Nasal colonization was sporadic and sparse . Colonization of trachea and lung was only observed with serotype A strains . The results showed that toxigenic P . multocida can colonize the upper respiratory tract, especially the tonsils, of pigs.

Can J Vet Res, 1990 Apr, 54 Suppl, S48 - 52
Molecular aspects of virulence of Pasteurella haemolytica; Confer AW et al.; Pasteurella haemolytica is represented by two biotypes (A and T), 15 serotypes, and numerous untypable strains . Specific biotypes and serotypes are associated with fibrinous pleuropneumonia (pneumonic pasteurellosis) in cattle, sheep, and goats, septicemic pasteurellosis in lambs, and mastitis in ewes . Four virulence factors have been associated with P . haemolytica: fimbriae, a polysaccharide capsule, endotoxin {lipopolysaccharide (LPS)}, and leukotoxin (LKT) . The interactions of these virulence factors with components of the pulmonary alveolus are discussed as a model for the pathogenesis of pasteurellosis . Fimbriae on P . haemolytica may enhance colonization of the upper respiratory tract . The capsule of P . haemolytica varies in composition among serotypes . It inhibits complement-mediated serum killing as well as phagocytosis and intracellular killing of P . haemolytica . The capsule enhances neutrophil directed migration and adhesion of P . haemolytica to alveolar epithelium . Pasteurella haemolytica LPS can alter bovine leukocyte functions, by dose-dependent inhibition or augmentation; it is directly toxic to bovine endothelium; it modifies cardiopulmonary hemodynamics; and it elevates circulatory prostanoids, serotonin, cAMP, and cGMP . Leukotoxin is produced by all known serotypes and many untypable strains . Leukotoxin is a poreforming cytolysin that affects ruminant leukocytes and platelets by altering function at low levels but causing lysis at high levels.

Vet Microbiol, 1990 Apr, 22(2-3), 259 - 66
The effect of Pasteurella haemolytica cytotoxin on bovine polymorphonuclear leukocytes can be attenuated by beta-adrenoceptor antagonists; Henricks PA et al.; It was investigated whether beta-adrenoceptor antagonists could disturb the interaction between cytotoxin preparations isolated from Pasteurella haemolytica and bovine polymorphonuclear leukocytes (PMNs) . The toxicity of the cytotoxin preparation was evaluated by measuring the chemiluminescence response and the viability of the cells after incubation with the cytotoxin . No effect on cell viability was detected when PMNs were incubated with 63 micrograms cytotoxin per ml while the chemiluminescence response was diminished by approximately 30% . The beta-adrenoceptor antagonists alprenolol (10(-5) M) and propranolol (5 X 10(-7) - 5 X 10(-6) M) were able to attenuate this effect of cytotoxin on the chemiluminescence response of PMNs . It seemed unlikely that propranolol and alprenolol diminished the effect of cytotoxin on the chemiluminescence response of PMNs by their beta-adrenoceptor blocking potency because other beta-adrenoceptor antagonists used were without effect . Also, the membrane stabilizing characteristics of the beta-adrenoceptor antagonists used were probably not responsible for the diminished interaction between PMNs and the cytotoxin . Whether beta-adrenoceptor antagonists could be used in vivo to prevent or treat P . haemolytica infections in bovines remains to be examined.

Vet Rec, 1990 Mar 10, 126(10), 231 - 2
Use of long-acting oxytetracycline against pasteurellosis in lambs; Appleyard WT et al.; The efficacy of long-acting oxytetracycline in the control of pneumonic pasteurellosis in lambs was tested on seven Scottish farms . After laboratory confirmation of pasteurella-related deaths in lambs, half the lambs in each flock were given long-acting oxytetracycline (20 mg/kg intramuscularly) and half were left untreated . On three farms a single treatment was given and on four farms two doses were administered four days apart . Eighteen of the 878 control lambs died as a result of confirmed Pasteurella haemolytica pneumonia compared with one of the 878 treated lambs . In addition nine of the control lambs were diagnosed clinically to have pasteurellosis which responded to treatment with oxytetracycline . None of the treated lambs were seen to be ill during the trial.

J Gen Microbiol, 1990 Mar, 136 ( Pt 3), 495 - 505
Characterization of envelope proteins from Pasteurella haemolytica and Pasteurella multocida; Knights JM et al.; A method was devised for the reproducible isolation of envelopes from Pasteurella haemolytica serotype A2 . It was also possible to prepare envelopes from other serotypes of P . haemolytica and Pasteurella multocida using this methodology . Examination of these preparations by SDS-PAGE showed major differences between strains of P . haemolytica and strains of P . multocida which allowed the clear distinction of isolates of these species . Amongst the P . haemolytica serotypes it was possible to distinguish envelope preparations made from A biotype and T biotype organisms easily, but it was not possible to identify individual serotypes from each other . Envelope profiles were sufficiently different between the individual P . multocida serotypes examined to allow each to be identified by its polypeptide profile . Experiments using radiolabelling, antibody absorption, and susceptibility to protease digestion, together with heat modifiability and detergent solubility characteristics indicated that 13 of the envelope proteins were probably surface-located . A high molecular mass immunogenic envelope protein was shown, by immunoblotting, to be present in all strains of P . haemolytica and P . multocida examined.

Am J Vet Res, 1990 Mar, 51(3), 433 - 8
Effect of Pasteurella haemolytica-derived endotoxin on pulmonary structure and function in calves; Slocombe RF et al.; The role of endotoxin in the pathogenesis of acute pneumonic pasteurellosis is uncertain . Recently, we reported that Escherichia coli-derived endotoxin given by airway inoculation fails to induce lung injury in calves . Because Pasteurella haemolytica-derived endotoxin may differ substantially from E coli in its pathogenicity, we repeated these studies with Pasteurella endotoxin . Intratracheal inoculation of P haemolytica endotoxin caused hypoxemia and increased the alveolar-arterial oxygen differences without causing hypercarbia or changes in lung mechanical properties and volumes . In contrast, IV inoculation of endotoxin caused systemic hypotension, leukopenia, gas exchange impairment, increased total pulmonary resistance, and decreased dynamic compliance . Both routes of inoculation increased serum endotoxin concentrations and were associated with areas of pulmonary hemorrhage, edema, and acute inflammation . We concluded that P haemolytica-derived endotoxin is pathogenic by IV and airway routes of inoculation, and therefore differs from E coli endotoxin in its ability to induce lung lesions in calves.

Infect Immun, 1990 Mar, 58(3), 828 - 32
Nonreciprocal complementation of the hlyC and lktC genes of the Escherichia coli hemolysin and Pasteurella haemolytica leukotoxin determinants; Forestier C et al.; The genetic organization of the Pasteurella haemolytica leukotoxin operon (lktCABD) is similar to that of the Escherichia coli hemolysin (hlyCABD) . Their gene products share a sequence similarity of 66, 62, 90.5, and 75.6%, respectively . We investigated the role of the C proteins (LktC and HlyC) by performing reciprocal transcomplementation analyses in an E . coli recombinant background . In the absence of the C genes, neither LktA nor HlyA had their respective cytotoxic activities . When hlyC was provided in trans to lktA, the toxin that was produced had the same activity and target cell specificity as the wild-type leukotoxin; it was leukotoxic for bovine lymphoid cells but not human lymphoblast cells when it was evaluated by a 51Cr-release assay . We also detected a weak hemolytic activity for the active form of LktA against sheep erythrocytes . In contrast, an E . coli strain containing lktC with hlyA produced a form of HlyA which was neither hemolytic nor cytotoxic . A monoclonal antibody (D12) against HlyA which recognized an epitope specific to the active form of HlyA did not cross-react in immunoblots with LktA that was activated by either LktC or HlyC . We conclude that the mechanism for activation of leukotoxin and hemolysin by their respective C proteins (LktC and HlyC) is mechanistically similar but that the exact structural requirements involved in the process are different.

Vet Microbiol, 1990 Mar, 22(1), 79 - 87
Possession of identical nonconjugative plasmids by different isolates of Pasteurella multocida does not imply clonality; Ikeda JS et al.; Experiments were performed to test the hypothesis that possession of the same nonconjugative R plasmid by different isolates of Pasteurella multocida implied that they were of the same clone . Seven isolates of P . multocida were studied, two possessed an identical nonconjugative R plasmid (pVM109), four possessed another (pVM110), and one isolate possessed a nonconjugative R plasmid related to pVM110 . Phenotypic and genotypic characteristics of the isolates were determined and compared . Isolates possessing the same nonconjugative R plasmid were shown to be different, and isolates possessing a different nonconjugative R plasmid were shown to be the same . We conclude that possession of an identical nonconjugative R plasmid by two isolates of P . multocida does not imply clonality.

J Vet Pharmacol Ther, 1990 Mar, 13(1), 23 - 8
Effects of haemorrhagic septicaemia vaccination and levamisole administration on the humoral response in cross-bred calves; Sharma LK et al.; Levamisole administered by oral, subcutaneous or transdermal routes following vaccination against Pasteurella multocida enhanced the humoral response in cross-bred calves . The group that received levamisole subcutaneously elicited highly significant (P less than 0.01) antibody titres during the primary humoral response in comparison with groups that received levamisole orally or transdermally . During the secondary response in the same experiment, levamisole administered subcutaneously and transdermally showed highly significant (P less than 0.01) haemagglutination titres relative to oral administration of the drug . In a second experiment, the group that received levamisole subcutaneously showed highly significant (P less than 0.01) antibody titres during the anamnestic humoral response over other treated groups.

N J Med, 1990 Feb, 87(2), 127 - 9
Pasteurella multocida meningitis; Costa-Cruz O et al.; The diagnosis of Pasteurella multocida meningitis was confused by a false-positive latex particle agglutination test implicating group B streptococcus . This illness and false-positive reactions in antigen detection are discussed.

Postgrad Med J, 1990 Feb, 66(772), 125 - 6
Pasteurella pneumotropica: meningitis following a dog bite; Minton EJ; A 38 year old man developed meningitis following a dog bite . Pasteurella pneumotropica, usually an animal pathogen, was isolated from the cerebrospinal fluid . The patient made a complete recovery after antibiotic therapy . The relevant literature is reviewed.

Am J Physiol, 1990 Feb, 258(2 Pt 2), R536 - 42
Somnogenic, pyrogenic, and hematologic effects of experimental pasteurellosis in rabbits; Toth LA et al.; Previous work has demonstrated that intravenous inoculation of rabbits with various microorganisms induces complex time-dependent alterations in sleep as well as other pathophysiological effects typically associated with infectious disease . To evaluate the effects of bacterial challenge that more closely resembles naturally developing disease, we inoculated rabbits with Pasteurella multocida, a common pathogen of this species, using routes of administration that mimic normal routes of exposure . Biphasic sleep alterations characterized initially by enhanced slow-wave sleep and later by decreased slow-wave sleep occurred after intravenous, intramuscular, subcutaneous, or intranasal inoculation . Rapid-eye-movement sleep was inhibited for most of the 48-h period after inoculation . Inoculation by all four routes also induced fever and qualitatively similar hematologic changes . However, the magnitude and specific temporal patterns of both somnogenic changes and other pathophysiological effects varied with the route of inoculation.

Am J Vet Res, 1990 Feb, 51(2), 207 - 10
DNA fingerprinting for differentiation of field isolates from reference vaccine strains of Pasteurella multocida in turkeys; Kim CJ et al.; The genomes from field isolates of Pasteurella multocida in turkeys and those of P multocida reference CU and M9 vaccine strains were analyzed and compared after cleavage with restriction endonucleases . The electrophoretic profiles obtained with DNA fragments from field isolates and vaccine strains of the same serotype were characteristic and reproducible . These features indicated the existence of differences among the isolates of the same serotype that cannot currently be detected, using available serotyping methods . However, several field isolates had electrophoretic profiles similar to those of either CU or M9 vaccine strain . It was concluded that restriction endonuclease analysis of DNA genomes from P multocida isolated from turkeys provides the information for differentiation of field isolates from vaccine strains of the same serotype.

Vet Microbiol, 1990 Feb, 21(4), 363 - 75
The airborne survival of Pasteurella haemolytica and its deposition in and clearance from the mouse lung; Gilmour MI et al.; Pasteurella haemolytica A1 was aerosolised by a Collison nebuliser in a Henderson apparatus and its survival in air was measured . The organism was fragile in aerosol and survived best at high humidity and warm temperature . Mice were exposed to the aerosol and clearance from the lung measured . Deposition in the mouse lung showed a good linear correlation with bacterial concentration in the spray suspension fluid . Clearance from the lung was rapid over 24 h although some bacteria could be detected 2 and 4 days after exposure . Mice which received a second exposure 2 weeks later exhibited accelerated clearance from the lung whereby no bacteria could be detected after 12 h . This was associated with serum IgG antibody production, and local and splenic lymphocyte responses to bacterial antigen in vitro.

Immunol Cell Biol, 1990 Feb, 68 ( Pt 1), 57 - 61
Pasteurella multocida infections in mice with reference to haemorrhagic septicaemia in cattle and buffalo; Ramdani et al.; Haemorrhagic septicaemia (HS) is an infectious disease of cattle and buffalo caused by particular serotypes of Pasteurella multocida and is one of the most economically important livestock diseases in South-East Asia . While HS has been recognized for many years, very little is understood about the disease, primarily because of the expense of cattle and a lack of suitable animal models . The suitability of using mice to study HS was assessed using parameters such as the critical pathogenic dose, kinetics of infection, pathology of disease and resistance to reinfection . Pasteurella multocida M1404, the type strain for Carter group B, the serotype responsible for Asian HS, was injected intraperitoneally into BALB/c mice . As few as 20 colony forming units produced an overwhelming septicaemia in mice in less than 30 h . The kinetics of infection demonstrated a very rapid in vivo multiplication rate . There was no evidence of inhibition of bacterial cell growth by natural host defence mechanisms, even with the very small inocula used . The gross pathology of the disease in mice was characterized by splenomegaly, lymphadenopathy and petechial haemorrhages similar to that observed in cattle and buffalo with HS . Mice were found to develop a short-lived resistance to reinfection following a primary infection which had been successfully treated with antibiotics . The mouse would seem to provide an ideal tool by which to study HS, but warrant further studies in order to be able to critically assess it as a model for this economically important disease.

FEMS Microbiol Lett, 1990 Jan 15, 55(1-2), 187 - 90
Cloning and expression of the dermonecrotic toxin gene of Pasteurella multocida ssp . multocida in Escherichia coli; Kamps AM et al.; A DNA library of Pasteurella multocida ssp . multocida strain CVI 47459 was constructed in the Lambda GEM-11 vector . Recombinant clones that encoded dermonecrotic toxin (DNT) were identified immunologically with antiserum raised against purified DNT . By comparing the DNA restriction maps of the immunoreactive recombinants, we located the DNT gene . Hybridization studies with 10 strains of P . multocida ssp . multocida suggested that strains that do not produce the DNT do not contain sequences homologous to the DNT gene.

Vet Microbiol, 1990 Jan, 21(3), 283 - 90
Reduced microbicidal activity of peripheral mononuclear phagocytic cells infected with Pasteurella multocida; Truscott WM et al.; Pasteurella multocida inhibits the uptake and killing of Candida albicans and P . multocida by avian mononuclear phagocytic cells . The toxic outer membrane protein of P . multocida, which has been previously described, also inhibited the uptake and killing of C . albicans . Antibody specific for the toxic outer membrane protein reversed this effect resulting not only in an increase in uptake of C . albicans and P . multocida, but also in intracellular killing of P . multocida . This antibody, however, only partially restored killing of C . albicans . These data support the hypothesis that P . multocida is capable of intracellular survival in avian mononuclear phagocytic cells and that the toxic outer membrane protein is totally or partly responsible for this occurrence.

Br J Neurosurg, 1990, 4(3), 237 - 8
Pasteurella multocida: a rare case of shunt infection; Lee T et al.; Pasteurella multocida, the major pathogen following an animal bite, is a rare cause of intracranial infection . This report documents the first case of ventriculo-peritoneal shunt infection with Pasteurella multocida.

Arch Exp Veterinarmed, 1990, 44(2), 295 - 300
{Typing and virulence testing of Pasteurella haemolytica field strains}; Schimmel D et al.; The greater part of 145 typed Pasteurella haemolytica strains from calf could be attributed to Type A 1 . Hence, in the context of virulence testing, this is the most important type at present for calf . Clearly manifest pneumonia was caused in calf by other strains of Types A 2, A 6, A 12, and T 10 which were also tested for their virulence parameters . The same applied to a number of strains which had so far been characterised merely as T or A/T strains.

Vet Res Commun, 1990, 14(3), 175 - 80
Effects of Pasteurella haemolytica leukotoxin on neutrophils from white-tailed deer and several exotic ruminant species; Confer AW et al.; Pasteurella haemolytica leukotoxin is a pore-forming cytolysin which acts as a virulence factor in pasteurellosis of domestic ruminants . Leukocytes from cattle, sheep and goats are susceptible to leukotoxin-induced lysis; however, leukocytes from non-ruminant species so far tested are resistant to leukotoxin-induced lysis . Neutrophils obtained from three white-tailed deer, four Saiga antelope, an Addra gazelle, a Grant's gazelle and a Sable antelope were tested for susceptibility to the lytic effects of P . haemolytica leukotoxin using lactate dehydrogenase release . Results were compared to those obtained using neutrophils from a steer and cultured bovine lymphoma cells . Neutrophils obtained from all these ruminants, except the Addra gazelle, were susceptible to P . haemolytica leukotoxin . Individual variation among the Saiga and the deer did not appear to be due to the percentages of neutrophils or the percentage of contaminating erythrocytes in the cell preparations.

J Gen Microbiol, 1990 Jan, 136 ( Pt 1), 81 - 7
Cloning of the toxin gene from Pasteurella multocida and its role in atrophic rhinitis; Lax AJ et al.; The gene for the osteolytic toxin of Pasteurella multocida has been cloned into a plasmid vector and expressed off its own promoter in Escherichia coli . Particular restriction endonucleases failed to cut the gene and regions flanking it, suggesting an A + T base ratio significantly greater than the remaining genome of P . multocida . Cloned toxin was indistinguishable from the native toxin with respect to molecular mass, antigenicity and toxicity in different tests . A single intraperitoneal injection of toxin purified from the recombinant E . coli reproduced in gnotobiotic pigs the pathological changes characteristic of atrophic rhinitis . The recombinant E . coli produced at least 10 times as much toxin as P . multocida.

Arch Exp Veterinarmed, 1990, 44(1), 65 - 73
{Bactericides against Pasteurella multocida in whole blood, plasma and lung lavage fluid of untreated and immunized young swine and calves}; Muller G et al.; The investigation of bactericidal effects in the whole blood and plasma of young pigs and calves against Pasteurella multocida has shown that such effects only come into being or are activated during the direct interaction between the host and pasteurellae, with effects being increased in previously immunized animals . The same is true for the antibodies which are detectable by indirect haemagglutination . There is no bactericidal effect in the concentrated lung lavage fluid against pasteurellae.

Avian Dis, 1990 Jan-Mar, 34(1), 214 - 7
Alternative injection sites for a Pasteurella multocida bacterin; Glisson JR et al.; Seven different injection sites for a Pasteurella multocida bacterin were evaluated by measuring the immune response and the local tissue reaction . Injection into the ventral surface of the tail or subcutaneously along the dorsal midline of the neck were the most suitable procedures . Ease of application was judged subjectively, and the tail site was found to be easier to inject accurately than the subcutaneous neck site . The tail injection site was found to be the best overall when immune response, tissue reaction, and ease of application were all considered.

Avian Dis, 1990 Jan-Mar, 34(1), 193 - 5
Somatic serotypes of Pasteurella multocida strains isolated from avian hosts (1976-1988); Rhoades KR et al.; During the period of 1976-88, 733 strains of Pasteurella multocida isolated from avian hosts were submitted to the National Animal Disease Center for somatic serotyping . The serotypes were determined and are presented in a summarized form in this report . The most common serotypes were 3 (29%); 1 (18%); 3,4 (12%); and 3,4,12 (9%) . The 733 strains had been isolated from 25 species of avian hosts; 400 (55%) were from turkeys . The most common serotypes of strains from turkeys were 3 (38%); 3,4 (18%); 3,4,12 (11%); and 4 (4%).

Avian Dis, 1990 Jan-Mar, 34(1), 137 - 40
Turkey heterophil chemotaxis to Pasteurella multocida (serotype 3,4)-generated chemotactic factors; Latimer KS et al.; The purpose of this study was to determine the ability of three strains or isolates of Pasteurella multocida (serotype 3,4) to generate chemotactic factors for heterophils when exposed to pooled turkey serum . Results indicated that each bacterial strain or isolate (M-9, CU, and 86-1913) was associated with the production of chemotactic factors, but the more pathogenic bacterial isolate (86-1913) elicited greater heterophil migration in chemotaxis studies.

Can J Vet Res, 1990 Jan, 54(1), 170 - 3
Streptococcus suis infection in swine . A sixteen month study; Higgins R et al.; A total of 349 isolates of Streptococcus suis retrieved from different tissues from diseased pigs were examined in this study . Only 48% of them could be categorized as one of serotypes 1 to 8 and 1/2 . Among typable isolates, serotype 2 was the most prevalent (23%), followed by serotype 3 (10%) . The majority of all isolates originated from lungs, meninges/brain, and multiple tissues . Forty-one percent of typable isolates and 33% of untypable isolates were retrieved in pure culture . Other isolates were found in conjunction with Pasteurella multocida, Escherichia coli, Actinobacillus pleuropneumoniae, Actinomyces pyogenes, and other streptococci . Typable S . suis isolates were more frequently isolated from pigs between five and ten weeks of age, while untypable isolates were mostly found in animals aged more than 24 weeks . No obvious monthly and/or seasonal variation of the prevalence of isolation of S . suis could be detected.

Can J Vet Res, 1990 Jan, 54(1), 157 - 63
Host response to Pasteurella multocida turbinate atrophy toxin in swine; Williams PP et al.; A porcine strain of Pasteurella multocida (serotype D:3) produced a toxin causing turbinate atrophy (TA) in pigs . The toxin (TAT), processed on a high performance liquid chromatography size exclusion column, eluted as a single peak (molecular weight of about 160,000) containing trace amounts of endotoxin (lipopolysaccharide, LPS; protein:LPS, 85:1) . The eluted fraction migrated on sodium dodecyl sulfate polyacrylamide gels as a single band . It could be prevented from dissociating into two prominent polypeptides by addition of a protease inhibitor . A single dose (2.0 to 79.0 micrograms/kg) of TAT given to pigs intravenously was lethal . Doses from 0.02 to 1.0 microgram/kg caused transient clinical signs of porcine systemic toxicosis with reduced appetite, generalized weakness, depression, lethargy, weight loss, and in some instances, death . Intradermal doses of TAT (greater than or equal to 0.1 microgram/site) produced hemorrhagic areas within four hours . Systemically, TAT causes bilateral TA, lymphopenia, liver dysfunctions, and possible renal impairment . Affinity of TAT for cells of epithelial origin was demonstrated in mice given 125I-TAT . In vitro, TAT stimulated DNA and protein syntheses of peripheral blood lymphocytes and suppressed syntheses in turbinate and kidney cell cultures without being cytolytic . Biological effects of TAT were eliminated by exposure to either heat, trypsin or anti-TAT antibody.

Can J Vet Res, 1990 Jan, 54(1), 146 - 50
Granulocyte plasma membrane damage by leukotoxic supernatant from Pasteurella haemolytica A1 and protection by immune serum; Styrt B et al.; Bovine respiratory disease caused by Pasteurella haemolytica may be partially mediated by a leukotoxin secreted by the microorganism . We examined the effect of leukotoxic Pasteurella supernatants on leakage of the cytosol enzyme lactate dehydrogenase and the lysosomal enzyme arylsulfatase from bovine granulocytes . Lactate dehydrogenase release (94%) was much higher than arylsulfatase release (38%) over 30 minutes of incubation . The Pasteurella supernatants inhibited superoxide production by stimulated granulocytes at concentrations which also caused substantial cell death as measured by failure to exclude trypan blue . Both toxic effects were prevented by serum from aerosol-immunized calves, and protection appeared to be antibody-specific by comparison with fetal bovine serum or with serum absorbed against intact P . haemolytica . These findings suggest that the leukotoxin may selectively disrupt the granulocyte plasma membrane, and that antibody directed against a surface component of the microorganism is also capable of protecting against the leukotoxin effect.

Can J Vet Res, 1990 Jan, 54(1), 139 - 45
A guinea pig model of bovine pneumonic pasteurellosis; Morck DW et al.; The induction of pneumonic pasteurellosis in guinea pigs (Cavia porcellus) was examined . Specific pathogen free male guinea pigs were anesthetized and a tracheostomy performed to introduce 10(5), 10(4) or 10(3) Pasteurella haemolytica-A1 into the left principal bronchus . The surgical site was closed with tissue adhesive and staples and the animals were monitored for signs of respiratory tract infection . Within 24 hours after inoculation they became depressed, anorectic, pyretic and dyspneic . Fibrinous pleuropneumonia with prominent areas of necrosis and hemorrhage was present . Pericardial effusion was a frequent finding . There was infiltration of the pleura and alveoli with degenerate heterophils and macrophages, a hyperplastic mesothelium and fibrin exudation on the pleura and within alveoli . Hemorrhage, congestion, consolidation, edema and fibrin exudation were prominent in the hilar region of the lungs . Bacterial colonies were evident in all airways . More bacteria were recovered from infected lungs than were inoculated (p less than 0.05) indicating P . haemolytica was actively multiplying in the lungs . Hematological and clinical chemistry data were consistent with fibrinous pneumonia, however, blood cultures were positive for P . haemolytica in 61% (11/18) of animals sampled . Examination of pneumonic pasteurellosis in guinea pigs may be useful in studying pathogenetic and pathological features applicable to bovine pneumonic pasteurellosis (shipping fever pneumonia).

J La State Med Soc, 1990 Jan, 142(1), 27 - 9
Pasteurella multocida empyema: successful treatment with open thoracostomy; Bohner BJ et al.; Pasteurella multocida appears to be an uncommon pathogen in human thoracic empyema . The morbidity and mortality associated with these infections has been significant, presumably secondary to the elderly populations they affect, many with chronic lung disease and impaired pulmonary defenses . We report a case of pasteurella empyema treated with open thoracostomy and rib resection and advocate use of such a procedure early in the treatment of patients with this infection.

J Clin Microbiol, 1990 Jan, 28(1), 70 - 5
Pasteurella multocida and Bordetella bronchiseptica infections in rabbits; Deeb BJ et al.; The natural history of infection with Pasteurella multocida and Bordetella bronchiseptica in domestic rabbits was studied prospectively at a commercial rabbitry . At weaning, about 25% of rabbits had nasal infections with P . multocida and 75% had infections with B . bronchiseptica . Infection of weanling rabbits paralleled nasal infections of their dams . The proportion of rabbits with both infections increased with age . At 2 to 4 months old, about 50% of rabbits with P . multocida or P . multocida and B . bronchiseptica infections had upper respiratory disease (URD), whereas rabbits with B . bronchiseptica infection had no disease . In rabbits about 10 months old, 75% with P . multocida or P . multocida and B . bronchiseptica infections had URD, whereas virtually none with B . bronchiseptica infection had disease . Disease of the nares, paranasal sinuses, middle ears, and lungs was associated with P . multocida and not B . bronchiseptica infection . In adult rabbits with nasal P . multocida infection, with or without signs of URD, about 80% had concurrent infection of the paranasal sinuses and middle ears and 20% had infection of the bronchi and lungs . In rabbits without nasal P . multocida infection, 20 to 35% had P . multocida infection of the paranasal sinuses and middle ears . Weanling rabbits with and without P . multocida infection had similar immunoglobulin G (IgG) levels . In rabbits observed prospectively, the only antibody differences between those transiently and persistently infected with P . multocida were a diminished IgA response in nasal lavages and an earlier IgM response in sera of transiently infected rabbits . IgG levels increased with the duration of infection . There was no relationship between immunoglobulin levels and freedom from P . multocida infection.

J Clin Microbiol, 1990 Jan, 28(1), 103 - 7
Development and epidemiological applications of a bacteriophage typing system for typing Pasteurella multocida; Nielsen JP et al.; A bacteriophage typing system was developed for typing toxigenic and nontoxigenic strains of Pasteurella multocida . A phage set of 24 phages with different lytic spectra was isolated after mitomycin treatment of P . multocida strains, isolated mainly from pigs from herds with atrophic rhinitis . On a test set of 97 different strains isolated from pigs, these 24 phages were able to type 87% of the strains . The 97 test strains could be subdivided into 31 different types by reaction with the 24 phages . The reproducibility after subculture and storage of the strains was good (95%) . Phage typing of 217 toxigenic P . multocida field isolates from 37 pig herds predominately with clinically atrophic rhinitis resulted in 18 different phage types and an overall typability of 68% . Of 24 herds from which more than three isolates of toxigenic P . multocida were obtained, a single phage type was demonstrated in 5 herds, while in 9 herds a single phage type represented at least half of the isolates . The phage types in the remaining 10 herds revealed no dominating phage type . The phage typing system described appears to be a valuable epidemiological tool for studying the spread of P . multocida.

Microbiol Immunol, 1990, 34(9), 715 - 21
Drug resistance and R plasmids in Pasteurella multocida isolates from swine; Yamamoto J et al.; A total of 163 strains of Pasteurella multocida isolated from swine were examined for drug resistance and R plasmids . Strains resistant to sulfadimethoxine (Sar), ampicillin (Apr), streptomycin (Smr), kanamycin (Kmr), and chloramphenicol (Cpr) were found in 93.9, 1.8, 16.6, 1.2, and 10.4%, respectively . There were two patterns of drug resistance (Sar and SarCpr) in isolates from nasal cavities, and five patterns (Sar, SarSmr, SarSmrCpr, SarSmrApr, and SarSmrKmrCpr) in isolates from pneumonic lung specimens . Two isolates studied were proved to carry a nonconjugative R plasmid pJY2 or pJY8 with other unidentified plasmids, respectively . pJY2 (3.6 megadaltons) encoding resistance to SarSmr had one cleavage site for EcoRI or HindIII endonuclease and two sites for PstI endonuclease . pJY8 (5.5 megadaltons) encoding resistance to Sar SmrKmrCpr had one EcoRI site and two PstI sites.

What Is Dna?, What Is Biofilm?, What Is Water Purification?, What Is Antibiotic?, What Is Molecular Microbiology?, i, Microbe, r, Microbiology, i, Microorganisms, o, Microbes, s, Bacterium, n, Microorganism, n, Proteus, r, Bacteriological, o, Streptococci, n, Streptococci, s, Antimicrobials, n, Gram negative, e, Antimicrobial, o, Microbiological, o, Staphylococcus aureus, i, Antibiotic treatment, r, Microbial, r, S. cerevisiae, a, Burkholderia, a, Agrobacterium, a, Prokaryotes, s, Gram negative, o, Antimicrobial, s, Escherichia coli, s, Escherichia coli, c, Pseudomonas aeruginosa

Scientific Publications - Work Done by Microbiology Reader Bioscreen C
Agricultural Microbiology Anaerobic Microbiology Antimicrobial Susceptibility Artificial Atmosphere Bioassay of Antibiotics Biofilm Microbiology Bioreactor Technology Biotechnology Cell Biology Clinical Microbiology Environmental Microbiology Experiments with Yeast	Fermentation Food Microbiology Functional Genomics Gene Technology Growth Media Development Growth Rate and Lag Time Industrial Microbiology Medical/Pharmaceutical Field Microbiological Assay Microbiological Research Microbiology of Cosmetics go to a specific theme...	Military Microbiology Molecular Microbiology Mutagenicity and Genotoxicity Oral Microbiology Patents Postantibiotic Studies Soil Microbiology Spore Microbiology Veterinary Microbiology Waste/Wastewater Treatment Water Microbiology Wine Microbiology

� 2005 Transgalactic Ltd (manufacturer of Bioscreen C software) | Privacy Statement | P.O. Box 1393, 00101 Helsinki, Finland, phone: +358 9 85172920, fax: +358 9 8749481, e-mail: microbiology@bionewsonline.com

Last modified: May 25, 2005