| interaction of ruminant transferrins with transferrin receptors in bovine isolates of pasteurella haemolytica and haemophilus somnus. | the interactions of ruminant transferrins with receptors on bovine isolates of pasteurella haemolytica and haemophilus somnus were compared by growth studies and direct and competitive binding assays. isolates of p. haemolytica were capable of utilizing and binding transferrin from sheep, goat, or cattle, whereas isolates of h. somnus were capable of utilizing and binding only bovine transferrin. | 1992 | 1612764 |
| outer-membrane protein and lipopolysaccharide variation in pasteurella haemolytica serotype a1 under different growth conditions. | growth characteristics, as well as outer-membrane protein (omp) and lipopolysaccharide (lps) profiles in sds-polyacrylamide gels, of two serotype a1 isolates of pasteurella haemolytica were examined under different in vitro growth conditions. the two isolates were chosen as representatives of disease (s/c 82/1) and non-disease (w/d 83/4) isolates, respectively. the growth rates and final cell densities of both isolates increased as the degree of aeration increased. in particular, the final cell ... | 1992 | 1645128 |
| differential induction of tumor necrosis factor alpha in ovine pulmonary alveolar macrophages following infection with corynebacterium pseudotuberculosis, pasteurella haemolytica, or lentiviruses. | soluble mediators such as tumor necrosis factor alpha (tnf-alpha) may be important in the pathogenesis of many chronic pulmonary infections. we examined the ability of corynebacterium pseudotuberculosis, pasteurella haemolytica, and ovine lentiviruses (ovlv) to induce tnf-alpha secretion by pulmonary alveolar macrophages (pam). bronchoalveolar lavage cells, composed of greater than 90% pam, were obtained from normal sheep. bronchoalveolar lavage cells were cultured for 2, 24, 48, 72, or 168 h in ... | 1991 | 1652561 |
| clinical pharmacokinetics of parenterally administered danofloxacin in cattle. | danofloxacin is a new fluoroquinolone antibacterial, developed specifically for veterinary use. its in vitro activity and pharmacokinetic properties have been investigated to assess its potential for use in the therapy of respiratory disease in cattle. the minimum inhibitory concentration of danofloxacin against 90% (mic90) of contemporary european and north american field isolates of pasteurella haemolytica, pasteurella multocida and haemophilus somnus, the most important bacterial respiratory ... | 1991 | 1663562 |
| protective effect of inactivated bovine herpesvirus-1 in calves experimentally infected with bovine herpesvirus-1 and pasteurella haemolytica. | 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 pasteurell ... | 1991 | 1664970 |
| exposure of sheep to pasteurella haemolytica alters ex vivo pulmonary vascular smooth muscle alpha adrenergic responses: role of vascular endothelium. | 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 ... | 1991 | 1666196 |
| epitope specificity of the protective immune response induced by individual bovine herpesvirus-1 glycoproteins. | 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-infecte ... | 1990 | 1697722 |
| pasteurella haemolytica a1 purified capsular polysaccharide does not stimulate interleukin-1 and tumor necrosis factor release by bovine monocytes and alveolar macrophages. | 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 ... | 1991 | 1866893 |
| separable domains define target cell specificities of an rtx hemolysin from actinobacillus pleuropneumoniae. | the leukotoxin (lkta) from pasteurella haemolytica and the hemolysin (appa) from actinobacillus pleuropneumoniae are members of a highly conserved family of cytolytic proteins produced by gram-negative bacteria. despite the extensive homology between these gene products, lkta is specific for ruminant leukocytes while appa, like other hemolysins, lyses erythrocytes and a variety of nucleated cells, including ruminant leukocytes. both proteins require activation facilitated by the product of an ac ... | 1992 | 1729215 |
| experimental infection of dexamethasone-treated goats with pasteurella haemolytica a2. | sixteen goats either subjected to transport stress or without transport stress were treated with dexamethasone for 3 days prior to infection with p. haemolytica serotype a2 intranasally. the transport-stressed and dexamethasone-treated goats in the first group had various degrees of pulmonary lesions and the organism was re-isolated from the nasal cavity, lymph nodes and lungs. none of the goats treated with dexamethasone only were infected with p. haemolytica and had no lesions of pneumonic pas ... | 1991 | 1777800 |
| effect of pasteurella haemolytica saline capsular extract on bovine pulmonary endothelial cells. | the purpose of this in vitro study was to determine whether pasteurella haemolytica capsular extract (ce) damages bovine pulmonary endothelial cells (ec) directly or through neutrophil-mediated mechanisms. chromium 51-labeled ec were treated with the following variables: ce (1, 10, and 100 ng of protein/ml), ce and bovine neutrophils (10(6) cells/well), and ce and polymyxin b (500 u/ml). although only minimal damage to ec occurred by 5 hours after treatment, by 22 hours after treatment, the 10-n ... | 1991 | 1785721 |
| molecular chimerization of pasteurella haemolytica leukotoxin to interleukin-2: effects on cytokine and antigen function. | a chimeric recombinant protein composed of the lkta gene product from pasteurella haemolytica fused to bovine interleukin-2 (il-2) was made. the lkt-il-2 chimera was compared with recombinant bovine il-2 with regard to the ability to induce proliferative responses and lak cell activity in bovine peripheral blood mononuclear cells in vitro. in both instances, chimerization had no effect on il-2 activity. similarly, the lkt component was unaffected in its ability to induce an effective immune resp ... | 1992 | 1730490 |
| [pasteurella haemolytica serotypes in cattle]. | eight-two bovine pasteurella haemolytica strains were serotyped. the majority of the strains were isolated from calves which had died from fibrinous pneumonia and small numbers from cases of pleuritis, sepsis and abortion. a total of eight different serotypes were noticed. serotype a1 was found to be the most prevalent 37.8 per cent, followed by serotype a2 with 20.7 per cent. antibiotic resistance was found for sulfonamide, tetracycline and penicillin in about half of all strains. conventional ... | 1992 | 1733033 |
| application of multivariate analyses of enzymic data to classification of members of the actinobacillus-haemophilus-pasteurella group. | outer membrane vesicles and fragments from actinobacillus actinomycetemcomitans, actinobacillus lignieresii, actinobacillus ureae, haemophilus aphrophilus, haemophilus paraphrophilus, haemophilus influenzae, haemophilus parainfluenzae, pasteurella haemolytica, and pasteurella multocida were isolated and examined semiquantitatively for 19 enzyme activities by using the api zym micromethod. the enzyme contents of vesicles and fragments were compared with the enzyme contents of whole cells of the s ... | 1992 | 1736960 |
| in vitro antimicrobial susceptibility of pasteurella haemolytica and pasteurella multocida recovered from cattle with bovine respiratory disease complex. | 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 sulfachlorpyridazi ... | 1991 | 1892929 |
| further observations on enhancement of the infectivity of fusobacterium necrophorum by other bacteria. | it had already been shown with a single virulent strain (a42) of fusobacterium necrophorum that suspension of the fusobacteria in sub-lethal doses of broth cultures of other bacteria reduced the minimum infective dose (greater than 10(6) organisms) for mice by subcutaneous inoculation, sometimes to less than 10 organisms. the present study extended the known range of bacteria with strong infectivity-enhancing properties to include bacillus cereus, klebsiella oxytoca and staphylococcus aureus; an ... | 1991 | 1902184 |
| neutralizing monoclonal antibodies to pasteurella haemolytica leukotoxin affinity-purify the toxin from crude culture supernatants. | 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 cu ... | 1991 | 1753879 |
| association of a pasteurella haemolytica-like organism with enteritis in swine. | 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 moderat ... | 1991 | 1760465 |
| therapy of bovine bacterial pneumonia. | practical strategies for developing rational therapeutic regimens based on in vitro sensitivity and pharmacokinetic disposition are presented. special attention is given to pasteurella haemolytica, which is regarded as the most frequent cause of bovine bacterial pneumonia. bacterial-dependent and host-dependent causes of therapeutic failure and potentially valuable novel therapies and drug combinations are considered. | 1991 | 1760756 |
| crossed immunoelectrophoresis applied to representative strains from 11 different pasteurella species under taxonomic aspects. | crossed immunoelectrophoresis evaluated on a numerical basis revealed a close antigenic relationship between species of the genus pasteurella. by cluster analysis, 4 groups on similarity levels between 87% and 72% s could be separated which were connected by a minimum level of 69.5% s. one subgroup included all biovars or subspecies consisting of strains with mucoid growth. another feature governing the antigenic relationship seemed to be the host range of pasteurella species. despite a consider ... | 1991 | 1930562 |
| market stress-associated changes in serum complement activity in feeder calves. | classical hemolytic complement (c) of calves was analyzed during a protocol designed to imitate the usual market handling of feeder calves from the southeastern united states. serum c concentrations of the calves (n = 100 x 4 years) were evaluated on their farm of origin, on arrival at an auction market, on arrival at a feedyard, and during their first 4 weeks in the feedyard. complement concentrations (measured in ch50 units) were typically lowest at the farm of origin and highest when the calv ... | 1991 | 1785726 |
| pulmonary particle deposition and airway mucociliary clearance in cold-exposed calves. | 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 ... | 1991 | 1767989 |
| occurrence and diversity of plasmids in ovine isolates of pasteurella haemolytica. | 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 ser ... | 1991 | 1788485 |
| protective role of bovine neutrophils in pasteurella haemolytica-mediated endothelial cell damage. | the purpose of this study was to determine if pasteurella haemolytica can directly injure bovine pulmonary endothelial cells (ec) and if neutrophils have a beneficial or detrimental role in bacterium-ec interaction. various combinations of live p. haemolytica, heat-killed p. haemolytica, anti-p. haemolytica immune serum, polymyxin b, and bovine neutrophils were added to confluent monolayers of bovine ec. monitoring included determination of 51cr release from ec, phase microscopy, and transmissio ... | 1991 | 1937816 |
| genomic distribution of a serotype 1-specific antigen-coding dna fragment of pasteurella haemolytica. | 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 mu ... | 1991 | 1789017 |
| the effect of pasteurella haemolytica a1 leukotoxic culture supernate on the in vitro proliferative response of bovine lymphocytes. | 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 polycl ... | 1991 | 1949582 |
| preliminary investigation of the mechanism of inhibition of bovine lymphocyte proliferation by pasteurella haemolytica a1 leukotoxin. | 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 ... | 1991 | 1949583 |
| characterization and comparison of antimicrobial susceptibilities and outer membrane protein and plasmid dna profiles of pasteurella haemolytica and certain other members of the genus pasteurella. | the outer membrane protein (omp), plasmid, and antimicrobial resistance profiles of pasteurella haemolytica serotypes 1 through 12, a bovine isolate of p multocida, a chicken isolate of p multocida, and an unidentified pasteurella species of bovine origin were examined. isolates of p haemolytica serotypes belonging to the same biotype possessed similar omp profiles. biotype a isolates contained 2 prominent omp of 43 kilodaltons (kd) and 29 kd, whereas biotype-t serotypes contained 3 major omp of ... | 1991 | 1789515 |
| the microbial flora of the respiratory tract in feedlot calves: associations between nasopharyngeal and bronchoalveolar lavage cultures. | 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 ... | 1991 | 1790489 |
| an in vitro model system to evaluate pulmonary macrophage, endothelial cell, and neutrophil interactions. | 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 m ... | 1991 | 1793029 |
| in vivo expression of iron regulated outer-membrane proteins in pasteurella haemolytica-a1. | pasteurella haemolytica-a1 was grown in vitro under iron-rich conditions, iron-depleted conditions, and in vivo within a chamber implanted in the peritoneal cavity of a rabbit to determine if iron regulated outer-membrane proteins were expressed in vivo. the antigenicity of outer membrane (om) proteins from bacteria grown under these conditions was assessed by immunoblotting with pooled serum from convalescent bovine calves experimentally infected with p. haemolytica-a1 and serum from the implan ... | 1991 | 1816491 |
| molecular aspects of virulence of pasteurella haemolytica. | 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 ... | 1990 | 1972901 |
| the experimental production of mastitis in sheep by intramammary inoculation of pasteurella haemolytica. | acute mastitis was consistently produced in primiparous ewes by inoculation of the mammary gland, via the teat canal, with an isolate of pasteurella haemolytica, serotype a9, originating from a field case of ovine mastitis. mastitis developed following the inoculation of as few as 10 colony forming units of this isolate, suggesting that only a small number of organisms would be required to initiate the disease under natural conditions provided they were already beyond the teat canal. clinical si ... | 1991 | 1770180 |
| lymphocyte subpopulations in peripheral blood of lambs experimentally infected with pasteurella haemolytica. | 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 ... | 1991 | 1712143 |
| a neutral glycoprotease of pasteurella haemolytica a1 specifically cleaves o-sialoglycoproteins. | a neutral metalloprotease with marked specificity for an o-sialoglycoprotein has been isolated from culture supernatants of pasteurella haemolytica a1. the 35-kda enzyme cleaves human erythrocyte glycophorin a, which is o glycosylated, but does not cleave n-glycosylated proteins or nonglycosylated proteins. glycophorin a was cleaved when it was present in situ in erythrocyte ghost plasma membranes or when it was free in solution. the glycoprotease did not hydrolyze glycophorin a from which siala ... | 1992 | 1729196 |
| detecting nonhemolytic pasteurella haemolytica infections in healthy rocky mountain bighorn sheep (ovis canadensis canadensis): influences of sample site and handling. | 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. haemol ... | 1991 | 2023328 |
| aerobic bacteria from nasal discharge of goats suffering from clinical ppr: isolation and identification. | bacteriological isolation of aerobic bacteria from nasal discharge of achondroplastic west african dwarf goats showing clinical signs of peste des petits ruminants (ppr), and the laboratory procedures carried out for the identification of the isolates are described. from a total of forty nasal swabs obtained seventy five isolates were recovered. the percentage frequency of isolation of different organisms in descending order of occurrence is as follows: staphylococcus 44.0%; streptococcus 22.67% ... | 1991 | 2023545 |
| interaction of red deer leucocytes with pasteurella haemolytica leucotoxin. | | 1991 | 2024415 |
| the actinobacillus pleuropneumoniae hemolysin determinant: unlinked appca and appbd loci flanked by pseudogenes. | 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 ami ... | 1991 | 1860823 |
| [antibiotic sensitivity of pasteurella haemolytica in slaughter cattle]. | | 1991 | 1862499 |
| nucleotide sequence of the hemolysin i gene from actinobacillus pleuropneumoniae. | 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 re ... | 1991 | 1879928 |
| activation of bovine neutrophils by partially purified pasteurella haemolytica leukotoxin. | 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 o ... | 1991 | 1879935 |
| the effects of stressful exercise on leukocytes in cattle with experimental pneumonic pasteurellosis. | 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 a ... | 1991 | 1882513 |
| cloning, nucleotide sequence, and expression of the pasteurella haemolytica a1 glycoprotease gene. | 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 maxicell ... | 1991 | 1885539 |
| pasteurella haemolytica endocarditis. | 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. | 1991 | 1885915 |
| immunological properties of actinobacillus pleuropneumoniae hemolysin i. | 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 t ... | 1991 | 1887566 |
| isolation of pasteurella haemolytica from the nasal cavity of goats. | 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 ... | 1991 | 1913132 |
| effects of experimentally induced pasteurella haemolytica infection in dairy calves on the pharmacokinetics of flumequine. | 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-c ... | 1991 | 1920605 |
| comparison of four immune variables and pulmonary lesions of goats with intrapulmonary exposure and subsequent intrathoracic challenge exposure with pasteurella haemolytica. | 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 ... | 1991 | 1928902 |
| some unusual members of the family pasteurellaceae isolated from human sources--phenotypic features and genomic relationships. | twelve human isolates exhibiting the properties of the family pasteurellaceae but phenotypically deviating from established species, or resembling species of animal origin that are only rarely reported to occur in human materials, were checked for their identities by dna-dna hybridization. the collection consisted of one strain of actinobacillus lignieresii, two strains of actinobacillus hominis (mannose-positive), two hitherto undescribed actinobacillus or actinobacillus-like species, [pasteure ... | 1991 | 1930571 |
| increased susceptibility to pasteurella haemolytica in lambs infected with bovine respiratory syncytial virus. | 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 tha ... | 1990 | 2079556 |
| identification of rtx toxin target cell specificity domains by use of hybrid genes. | the escherichia coli hemolysin (hlya) and pasteurella haemolytica leukotoxin (lkta) are cytolytic toxins encoded by genes belonging to the recently described rtx gene family. these cytotoxins are, respectively, 1,023 and 953 amino acids in length and are encoded by genes within identically organized operons. they share 45% amino acid sequence identities but differ in their target cell specificities. in vitro-derived recombinant hybrid genes between hlya and lkta were constructed by using restric ... | 1991 | 1937778 |
| cytolysins of actinobacillus pleuropneumoniae serotype 9. | cytolysin i (clyi) and cytolysin ii (clyii), which are present in the culture supernatant of actinobacillus pleuropneumoniae serotype 9, are thought to play an important role in the pathogenesis of pig pleuropneumonia. the purpose of this study was to clone and characterize the genetic determinants of these cytolysins. cloning was accomplished by the screening of dna libraries for the presence of cytolytic activity and for the presence of dna sequences homologous to leukotoxin dna of pasteurella ... | 1991 | 1937809 |
| alterations in pulmonary morphology and peripheral coagulation profiles caused by intratracheal inoculation of live and ultraviolet light-killed pasteurella haemolytica a1 in calves. | 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 pulmo ... | 1991 | 1949506 |
| immunoperoxidase evaluation of the relationship between necrotic lesions and causative bacteria in lungs of calves with naturally acquired pneumonia. | an immunoperoxidase technique was used to study the relationship between the necrotic lesions and causative bacteria found in lungs of 53 calves that had naturally acquired pneumonia. four types of necrotic lesions were identified on the basis of morphologic characteristics as follows: type 1 had coagulation necrosis surrounded by a dense zone of numerous degenerated leukocytes; type 2 was similar to type 1, but the central area of the lesions was severely affected, had no alveolar architecture ... | 1990 | 2085224 |
| a field investigation of subclinical mastitis in sheep in southern england. | 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 p ... | 1991 | 1959012 |
| evaluation of combined pasteurella vaccines in control of sheep pneumonia. | 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 l ... | 1991 | 1959015 |
| expression and kinetics of induced procoagulant activity in bovine pulmonary alveolar macrophages. | 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 lipopolysacchari ... | 1991 | 1959504 |
| the effect of pasteurella haemolytica cytotoxin on bovine polymorphonuclear leukocytes can be attenuated by beta-adrenoceptor antagonists. | 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 chemiluminescen ... | 1990 | 1972305 |
| efficacy of recombinant leukotoxin in protection against pneumonic challenge with live pasteurella haemolytica a1. | 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 s ... | 1991 | 1987075 |
| changes in blood and bronchoalveolar lavage fluid components in calves with experimentally induced pneumonic pasteurellosis. | 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 la ... | 1991 | 2012347 |
| identification and localization of an iron-regulated 35 kda protein of pasteurella haemolytica serotype a2. | 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 exp ... | 1991 | 1826734 |
| molecular studies of ssa1, a serotype-specific antigen of pasteurella haemolytica a1. | a serotype-specific antigen of pasteurella haemolytica a1 encoded on the recombinant plasmid pssa1 is characterized. nucleotide sequence analysis of the insert dna in pssa1 identified the gene ssai, which codes for a protein of approximately 100 kda. in vivo labeling of pssa1-encoded protein in escherichia coli maxicells showed the expression of a 100-kda protein from the insert dna on the recombinant plasmid. northern blot and primer extension analyses were used to identify the mrna transcript ... | 1991 | 1840576 |
| the role of leukocytes in the pathogenesis of fibrin deposition in bovine acute lung injury. | 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 ... | 1991 | 2024707 |
| a group level analysis of the associations between antibodies to seven putative pathogens and respiratory disease and weight gain in ontario feedlot calves. | 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 ye ... | 1990 | 2165846 |
| sequence and molecular characterization of the rob-1 beta-lactamase gene from pasteurella haemolytica. | the rob-1 beta-lactamase-encoding plasmids from eight pasteurella and two haemophilus strains were compared by restriction endonuclease and hybridization analyses. two types of rob-1-encoding plasmids, which differed in size, were detected. one (4.1 kb) was found only in pasteurella strains. the other (4.4 kb) was found in both haemophilus influenzae and in one of the eight pasteurella strains examined. these two plasmids shared multiple homologous fragments, suggesting that one was derived from ... | 1991 | 2024956 |
| interaction of bovine alveolar macrophages with pasteurella haemolytica a1 in vitro: modulation by purified capsular polysaccharide. | 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 macroph ... | 1991 | 2031303 |
| secretion and expression of the pasteurella haemolytica leukotoxin. | 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 l ... | 1990 | 2185213 |
| lysis of bovine platelets by pasteurella haemolytica leukotoxin. | 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 an ... | 1991 | 2035922 |
| molecular characterization of cytotoxins produced by haemophilus, actinobacillus, pasteurella. | the leukotoxin of pasteurella haemolytica has been implicated as one of the major virulence factors contributing to the pathogenesis of bovine pneumonic pasteurellosis. to gain a better understanding of the various biochemical, antigenic and toxigenic properties of the toxin, the genetic determinant (lkt) which encodes the leukotoxin has been cloned from p haemolytica serotype 1. results from the molecular characterization of this determinant showed that four genes are required to synthesize and ... | 1990 | 2193701 |
| interactions of haemophilus-actinobacillus-pasteurella bacteria with phagocytic cells. | the haemophilus-actinobacillus-pasteurella (hap) group of bacteria contains a number of important veterinary and human pathogens. although each species has specific characteristics and host range, most share the general property of being resistant to cellular defense mechanisms. in some cases (e.g. pasteurella multocida, pasteurella haemolytica and actinobacillus pleuropneumoniae) resistance results in part from the presence of an antiphagocytic capsule that protects the bacilli against ingestio ... | 1990 | 2193702 |
| positive and negative aspects of host immune response to haemophilus, actinobacillus and pasteurella. | haemophilus somnus, actinobacillus pleuropneumoniae and pasteurella haemolytica are economically important bacteria with pathogenic characteristics that require us to look further than killed, whole cell bacterins for induction of a protective immune response. a strong immune response is not synonymous with protection and the extreme specificity of the immune response works to our disadvantage when broad protection is needed. detection of animals that are susceptible or immune to infection is im ... | 1990 | 2193703 |
| comparison and analysis of the nucleotide sequences of pilin genes from haemophilus influenzae type b strains eagan and m43. | previous studies have demonstrated antigenic differences among the pili expressed by various strains of haemophilus influenzae type b (hib). in order to understand the molecular basis for these differences, the structural gene for pilin was cloned from hib strain eagan (p+) and the nucleotide sequence was compared to those of strains m43 (p+) and 770235 b0f+, which had been previously determined. the pilin gene of hib strain eagan (p+) had a 648-bp open reading frame that encoded a 20-amino-acid ... | 1991 | 2037360 |
| interaction of bovine neutrophils in pasteurella haemolytica mediated damage to pulmonary endothelial cells. | 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-tr ... | 1991 | 2038823 |
| cloning and expression of a 30 kda surface antigen of pasteurella haemolytica. | 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 wester ... | 1991 | 2048283 |
| vaccine containing iron-regulated proteins of pasteurella haemolytica a2 enhances protection against experimental pasteurellosis in lambs. | 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 ... | 1991 | 2058262 |
| experimental pneumonia in mice produced by combined administration of bordetella parapertussis and pasteurella haemolytica isolated from sheep. | 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 ... | 1991 | 2061424 |
| 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. | 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), w ... | 1990 | 2223608 |
| pasteurella haemolytica is highly sensitive to ultraviolet irradiation. | 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 ... | 1991 | 2067555 |
| the susceptibility of in vivo-grown pasteurella haemolytica to ovine defence mechanisms in vitro. | 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 ... | 1990 | 2073409 |
| time and temperature dependence of granulocyte damage by leucotoxic supernatants from pasteurella haemolytica a1. | 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 t ... | 1990 | 2079620 |
| deletion analysis resolves cell-binding and lytic domains of the pasteurella leukotoxin. | 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 ... | 1990 | 2082150 |
| hematological changes in calves exposed to a mixture of lipopolysaccharide and crude leukotoxin of pasteurella haemolytica. | 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. haemo ... | 1990 | 2249175 |
| summer mastitis caused by pasteurella haemolytica. | | 1990 | 2260270 |
| distribution of glycoprotease activity and the glycoprotease gene among serotypes of pasteurella haemolytica. | | 1990 | 2083719 |
| the efficacy of danofloxacin in the therapy of pneumonia associated with pasteurella species in housed calves. | 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/sulp ... | 1990 | 2088707 |
| monoclonal antibody in the identification of haemophilus somnus. | electrophoretic comparisons of outer membrane proteins of haemophilus somnus isolates revealed 2 major protein bands (46 and 14 kilodaltons [kd]) common to all isolates tested. a monoclonal antibody raised against h. somnus reacted to the 46-kd band. coagglutination tests were performed using a monoclonal antibody coagglutination assay. the monoclonal reagent was produced by incubating cowan strain staphylococcus aureus suspension, used as a source of crude protein a, with mouse ascitic fluid mo ... | 1990 | 2094432 |
| receptors for transferrin in pathogenic bacteria are specific for the host's protein. | transferrin receptors detected by a solid-phase binding assay were shown to be specific for the host's transferrin in the representative bacterial pathogens neisseria meningitidis (human), pasteurella haemolytica (bovine), and actinobacillus pleuropneumoniae (porcine). consistent with the receptor specificity, iron-deficient bacteria were only capable of utilizing transferrin from the host as a source of iron for growth. | 1990 | 2110858 |
| plasma disposition and tolerance of aditoprim in horses after single intravenous injection. | 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 c ... | 1990 | 2116704 |
| pasteurella haemolytica lipopolysaccharide-induced arachidonic acid release from and neutrophil adherence to bovine pulmonary artery endothelial cells. | 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 meta ... | 1990 | 2122778 |
| nonreciprocal complementation of the hlyc and lktc genes of the escherichia coli hemolysin and pasteurella haemolytica leukotoxin determinants. | 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 ... | 1990 | 2307519 |
| the effect of stress on host defense system and on lung damage in calves experimentally infected with pasteurella haemolytica type a1. | 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 ... | 1990 | 2123055 |
| morphological and morphometrical analysis of the acute response of the bovine alveolar wall to pasteurella haemolytica a1-derived endotoxin and leucotoxin. | 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 o ... | 1991 | 2019673 |
| resistance to trimethoprim and 2,4-diamino-6,7-diisopropyl-pteridine (0/129) in pasteurella haemolytica. | 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 ... | 1991 | 2024433 |
| protective effect of inactivated pasteurella haemolytica bacterin challenged in bovine herpesvirus-1 experimentally infected calves. | 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 ( ... | 1990 | 2168606 |
| pasteurella haemolytica as a co-pathogen in pullets and laying hens. | 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. | 1990 | 2177972 |
| isolation of pasteurella haemolytica from tonsillar biopsies of rocky mountain bighorn sheep. | 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 b ... | 1990 | 2338725 |
| immunohistochemical localization of pasteurella haemolytica a1-derived endotoxin, leukotoxin, and capsular polysaccharide in experimental bovine pasteurella pneumonia. | 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 elec ... | 1990 | 2191489 |
| new diagnostic techniques: a review of the hap group of bacteria. | pasteurella haemolytica, pasteurella multocida, haemophilus somnus, haemophilus parasuis and actinobacillus pleuropneumoniae cause considerable economic loss in the cattle and swine industries. the literature relating to diagnostic procedures for these infections is reviewed. both conventional and newer techniques are appraised in relation to the identification and classification of isolates, and to serological testing. | 1990 | 2193708 |
| specificity of bovine serum antibody to capsular carbohydrate antigens from pasteurella haemolytica. | 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 bacteriologi ... | 1990 | 2199487 |