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S Rosendal

Publications and source records attributed to S Rosendal.

At least 73 records · Page 4Linked to original sources
PubMed1987

Analysis of major antigens of Haemophilus (Actinobacillus) pleuropneumoniae and related organisms.

Outer membrane protein (OMP)-enriched extracts and whole-cell protein preparations of Haemophilus (Actinobacillus) pleuropneumoniae and related organisms were examined by polyacrylamide gel electrophoresis and immunoblotting. Both the OMP-enriched and whole-cell protein profiles of Actinobacillus suis, A. pleuropneumoniae (NAD-independent biovar), A. lignieresii, and Pasteurella haemolytica were very similar to those of H. pleuropneumoniae serotypes 1 to 8. Antisera prepared against H. pleuropneumoniae typically recognized three major OMP antigens with approximate molecular weights of 17,000 (17K), 32K, and 42K in immunoblots of H. pleuropneumoniae serotypes 1 to 8, Actinobacillus spp., and P. haemolytica. Antisera prepared against Actinobacillus spp. and Haemophilus sp. "minor group" also recognized these 17K, 32K, and 42K antigens. Using absorbed sera, we demonstrated that the 17K antigen had an epitope (or epitopes) common to all the gram-negative organisms examined, including Escherichia coli. The 32K and 42K antigens had epitopes common to members of the family Pasteurellaceae but, in the case of the 32K antigen, also contained unique epitopes. These results provide a basis for understanding the lack of specificity of serodiagnostic tests for H. pleuropneumoniae infection and provide another line of evidence for the association of H. pleuropneumoniae with the genus Actinobacillus.

Actinobacillus↗
PubMed1987

Phagocytic function of equine neutrophils exposed to Mycoplasma felis in vitro and in vivo.

Neutrophils were isolated from the peripheral blood of adult equids (group 1) and were purified on a density gradient of polyvinylpyrrolidone-coated silica gel. A bactericidal assay was developed, using an equine skin isolate of Staphylococcus epidermidis as target bacterium in medium containing pooled fresh equine serum for opsonization. Significant (P less than 0.05) killing was observed after 60 or 120 minutes' incubation. Reduction in bactericidal function of blood neutrophils was not found after incubation with a virulent strain of Mycoplasma felis for 30 or 60 minutes. Similarly, the function of blood and pleural neutrophils of ponies with M felis-induced pleuritis (group 2) was not different from the function of similar neutrophils from sham-inoculated control ponies (group 3). The number of viable M felis organisms was markedly reduced in the presence of fresh equine serum and equine-specific antibodies, but not when the serum was heat inactivated. Equine neutrophils did not phagocytize M felis. Seemingly, M felis did not impair bactericidal activity of equine neutrophils. Therefore, this mechanism does not predispose equids to bacterial pleuritis.

Animals↗
PubMed1987

In vitro exposure of bovine morulae to Ureaplasma diversum.

Ureaplasma diversum has been associated with infertility in the cow experimentally and in naturally occurring cases. However, the pathogenic mechanism is undetermined. The purpose of this study was to determine whether ureaplasmas are pathogenic for bovine morulae in vitro. Twenty-one morulae were recovered from three superovulated, mature, Holstein cows six or seven days postestrus. The embryos were divided into three groups (A,B,C) and incubated for 16 hours at 37 degrees C in humidified air with 10% CO2. Group A was incubated in embryo culture medium alone, Group B was incubated in culture medium with sterile ureaplasma broth added and Group C was incubated in culture medium containing 1.7 X 10(6) colony forming units Ureaplasma diversum strain 2312. After incubation, the morulae were examined using an electron microscope. Structures morphologically identical to U. diversum were present on the outer surface of the zonae pellucidae of all the morulae exposed to the organism and none were present on the unexposed control embryos. No other morphological differences were observed in either the ureaplasma-exposed embryos or the two groups of control embryos. Ureaplasma diversum was isolated from three of the five embryos incubated in culture medium with sterile ureaplasma broth added. These three embryos were recovered from one donor cow which cultured positive for U. diversum from the vulva and flush fluid. This finding suggests that the contaminating organisms entered the embryo culture wells either in the embryo collection medium or attached to the embryos.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Evaluation of growth of avian mycoplasmas on bile salt agar and in bile broth.

All nine Mycoplasma iowae strains and one strain of M gallinarum grew on 0.05 per cent 'bile' agar medium. The colony size of M iowae on this agar medium was similar to the size obtained on bile-free mycoplasma agar. One strain each of M maculosum, M arginini and M bovis also grew on 0.05 per cent bile agar. However, one strain each of M gallisepticum and M meleagridis were inhibited at this concentration. Six of the nine strains of M iowae were also resistant to 1 per cent 'bile' in broth medium but all were resistant to 0.5 per cent. The resistance of M iowae to 0.5 per cent 'bile' in broth may be a useful characteristic for differentiating it from some of the other avian mycoplasmas.

Agar↗
PubMed1986

Detection of antibodies to Mycoplasma felis in horses.

Mycoplasma felis has been isolated from horses with pleuritis, and limited research indicates that mycoplasma pleuritis can be reproduced in horses. The serodiagnostic potential of the indirect hemagglutination and the metabolism-inhibition tests was evaluated by testing 177 horses for antibodies to M felis. Seven horses with M felis pleuritis developed antibodies, and 6 horses with sterile or bacterial pleuritis had high titers suggesting a previous M felis infection. Six horses with pleuritis (one sterile and five bacterial) had low or no titers to M felis. Only one of 30 horses with conditions other than respiratory diseases seroconverted during hospitalization and the remaining horses had low titers. Seventy-eight foals, 4 to 6 months old, from one farm did not have titers, whereas 7 out of 50 yearlings from the same farm had high titers in the indirect hemagglutination test and titers in the metabolism-inhibition test. It appears that both tests are suitable for serodiagnosis of M felis infection in horses.

Animals↗
PubMed1986

Protective efficacy of capsule extracts of Haemophilus pleuropneumoniae in pigs and mice.

Capsular extracts of Haemophilus pleuropneumoniae, Serotype 1, were mixed with AL(OH)3 gel (3 parts extract + 1 part Al(OH)3) and used as vaccines in pigs and mice. Four preparations were tested in Experiment I: NaCl and Cetavlon (hexadecyltrimethyl ammonium bromide) extracts of both low in vitro passage (LP) and high in vitro passage (HP) culture, respectively. Four pigs vaccinated with the NaCl extract of the LP strain survived, whereas one of four from each of the remaining vaccine groups and five of six from the control group died. All vaccines induced complement-fixing antibodies. No apparent boosting of titres occurred as a result of challenge with live bacteria. Mice were vaccinated in Experiment II with NaCl and Cetavlon extracts of the LP strain. Both were protective, although the Cetavlon vaccine appeared more efficacious than the NaCl extract. The use of Al(OH)3 adjuvant improved the efficacy of the NaCl vaccine in mice. In Experiment III six gnotobiotic pigs were vaccinated with a combined NaCl and Cetavlon vaccine and seven animals were given placebo. In Experiment IV seven specific pathogen-free (SPF) pigs were given the combined vaccine and eight pigs received placebo treatment. Both of these experiments indicated that the extract vaccines did not completely protect but reduced the mortality in pigs challenged with homologous virulent H. pleuropneumoniae bacteria. The results indicate that capsular antigens of H. pleuropneumoniae have some protective immunogenic efficacy in pigs and mice.

Animals↗
PubMed1986

Experimental pneumonia in rabbits inoculated with strains of Pasteurella multocida.

Domestic rabbits were inoculated with either a 3:A or 3:D serotype of Pasteurella multocida by aerosol, intravenous, or intratracheal inoculation. Different colony forming units of P. multocida were used. Animals which died or were killed after the 14 day observation period were examined macroscopically and microscopically for lesions in the lower respiratory tract. Pneumonic lesions were most consistently produced in rabbits inoculated intratracheally with serotype 3:A. Pulmonary and pleural lesions were observed in some animals inoculated intravenously with serotype 3:A. Lesions were minimal in rabbits inoculated with serotype 3:D. Of the three routes of inoculation evaluated, the intratracheal route appeared to be the best method to produce Pasteurella-associated lesions in the lower respiratory tract.

Animals↗
PubMed1986

Experimental studies on the pathogenicity of Mycoplasma ovipneumoniae and Mycoplasma arginini for the respiratory tract of goats.

Mycoplasma ovipneumoniae and Mycoplasma arginini were the species of Mollicutes most commonly isolated from 175 goats with respiratory disease in Ontario. The pathogenicity of M. ovipneumoniae, strain B321B and M. arginini, strain D53e, was assessed in goats following endobronchial inoculation. One out of three two year old goats developed fever after inoculation with a pure culture of strain B321B, and it had extensive subacute fibrinous pleuritis when necropsied three weeks later. Neither of the remaining goats had lesions in the respiratory tract. Mycoplasma ovipneumoniae was recovered from one of the animals four days after inoculation, but not at necropsy from any of the goats, at which time a marked humoral immune response with growth inhibiting antibodies was detected. In a second experiment three four to five week old goats were inoculated with the same strain and three other goats were given placebo treatment. One experimental goat developed fever and coughing, and it had extensive subacute fibrinous pleuritis in the right side and pneumonia. Another goat had focal pneumonia in the left diaphragmatic lobe. Microscopically there was subacute hyperplastic suppurative bronchiolitis, atelectasis and nonsuppurative alveolitis. The infected animals did not clear the mycoplasma and not all of them produced antibodies. Mycoplasma arginini, strain D53e, did not induce lesions in any of four goat kids within 14 days after inoculation but did cause transient elevations in rectal temperature, circulating monocytes, circulating neutrophils and blood fibrinogen. Mycoplasma arginini was infective and immunogenic for all inoculated animals and showed a particular affinity for the tonsil. Thus, this study provides the first evidence that M. ovipneumoniae is pathogenic for goats causing pneumonia and pleuritis.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Streptococcus suis in slaughter pigs and abattoir workers.

The detection and identification of Streptococcus suis type 2 in 8.1% of 347 pig herds of southwestern Ontario revealed that the infection is widespread in this area. A herd suspected to be infected showed a carrier rate of 9.7% among the 62 animals sampled. These subclinical carriers represent a potential source of infection for slaughterhouse workers. From studies of contamination of hands and knives, it was concluded that eviscerators involved in removing the larynx and lungs from the carcasses have a significantly higher (p less than or equal to 0.05) risk of exposure to Streptococcus suis than other abattoir workers.

Abattoirs↗
PubMed1986

The association between serological evidence of mycoplasma infection and respiratory disease in feedlot calves.

Calves from five Ontario feedlots were bled on arrival and approximately 28 days later. Calves treated during this interval for undifferentiated respiratory disease were classified as cases and untreated calves were classified as controls. Serum was titrated blindly for antibodies to Mycoplasma bovis and Mycoplasma dispar. Indirect hemagglutination titers of 1:20 or more were assumed to reflect recent or current exposure, whereas 1:10 or less were not. The titers to M. bovis increased in all feedlots indicating active infection. The initial titers to M. dispar were higher than the titers against M. bovis, yet they increased in all feedlots except one, suggesting widespread infection with this organism. There was an increased risk (although not statistically significant) of being treated if the titer against M. bovis rose during the period. Calves with low M. dispar titers on arrival were at increased risk of being treated and titer increases were strongly associated with treatment (statistically significant). Thus, the serological results indicate high prevalence of M. bovis and M. dispar in the feedlot calves and that calves with increasing titers in particular to M. dispar are at increased risk of being treated for respiratory disease.

Animals↗
PubMed1986

Isolation of Streptococcus suis using a selective medium.

A selective medium containing tryptic soy agar, 5% defibrinated bovine blood, crystal violet, nalidixic acid and gentamicin significantly improved the isolation rate of Streptococcus suis from tonsilar tissue of slaughtered pigs. Ninety-five percent of the S. suis isolates identified in Guelph were confirmed as S. suis in Copenhagen, but only six out of 21 isolates typed as capsular serotype 2 in Guelph were confirmed to possess serotype 2 antigen in Copenhagen. Sixty-four percent of the S. suis isolates were not typable within the current scheme of capsular serotypes from 1 to 13 and type 1/2.

Animals↗
PubMed1985

Gastritis in Lake Tanganyika cichlids (Tropheus duboisii).

Necrotic and granulomatous gastritis is described in Lake Tanganyika cichlids. Clostridium hastiforme and flagellated protozoa were both associated with the reaction but the significance of either is unknown. Nevertheless, treatment of surviving fish with ampicillin was carried out and mortalities ceased. The possible involvement of an unsuitable diet as a predisposing factor is discussed.

Aeromonas↗
PubMed1985

Biochemical and serological identification of strains of Haemophilus pleuropneumoniae.

Eighteen field isolates of Haemophilus pleuropneumoniae were studied biochemically and serotyped using the complement fixation test (CFT), agglutination test and the immunodiffusion test. Three biochemical tests (V-dependency, CAMP-reaction and urease activity) were found to be very useful for the biochemical characterization of the H. pleuropneumoniae. Haemolysis on blood agar plates, although present, was not sufficiently pronounced in all cases to warrant absolute dependence on this characteristic. Serological typing revealed the isolates belong to Serotypes 1 and 5. The immunodiffusion test proved to be the most serotype specific, while a marked cross-reaction was observed with the CFT.

Agglutination Tests↗
PubMed1985

Serological cross-reactivity between a porcine Actinobacillus strain and Haemophilus pleuropneumoniae.

During serological screening of a closed SPF-herd free of pleuropneumonia, more than half of the pigs were positive for complement-fixing antibodies to Haemophilus pleuropneumoniae. Actinobacillus bacteria closely related to A. suis were isolated from tonsillar tissue of 14 out of 20 slaughtered pigs submitted for pathological and bacteriological evaluation. None of the pigs had evidence of respiratory disease. Two pigs inoculated endobronchially with a selected Actinobacillus strain developed mild focal pneumonia and complement-fixing antibodies cross-reacting with H. pleuropneumoniae. Five pigs exposed and vaccinated with the Actinobacillus strain and five pigs spontaneously infected with the strain also developed complement-fixing antibodies against H. pleuropneumoniae and appeared to be less susceptible to experimental Haemophilus pleuropneumonia than pigs not exposed to the Actinobacillus infection. The agglutination test applied on serum treated with 2-mercaptoethanol detected antibodies against H. pleuropneumoniae serotype 5 but not against serotype 1 in pigs exposed to the Actinobacillus strain. Antibodies reactive with the Actinobacillus strain were also found in pigs hyperimmunized against H. pleuropneumoniae serotypes 1-5 in 2-mercaptoethanol tube agglutination test and rabbits hyperimmunized against serotypes 1,2 and 7, and strain 73567 in the immunodiffusion test. Conversely rabbits immunized against the Actinobacillus strain had antibodies against H. pleuropneumoniae serotypes 1, 3, 4, 5 and 6. It is concluded that pigs infected with Actinobacillus organisms may become false positive reactors against H. pleuropneumoniae.

Actinobacillus↗
PubMed1985

Comparative virulence of porcine Haemophilus bacteria.

The virulence of strains of Haemophilus pleuropneumoniae serotype 1, 2, 3, 7 and strains of the "minor-group" and Haemophilus parasuis were compared by inoculating specific pathogen-free pigs into the lower airways with specified doses of bacteria. Haemophilus pleuropneumoniae, strain W, serotype 1, given in 1 X 10(8) colony-forming units, produced a lethal acute pleuropneumonia in four pigs. Nonlethal localized pulmonary necrosis was induced in four groups of two pigs given 1 X 10(7), 1 X 10(6), 1 X 10(5) and 1 X 10(4) respectively of the same strain. Two groups of four pigs developed chronic lesions when inoculated with 1 X 10(7) colony-forming units of H. pleuropneumoniae, strain Shope 4074, serotype 1 and 1 X 10(7) colony-forming units of H. pleuropneumoniae, strain WF83, serotype 7, respectively. Of 20 pigs given 1 X 10(8) colony-forming units of strain 1536, serotype 2, two died of acute pleuropneumonia and 18 had lesions of pulmonary necrosis or abscessation and pleuritis. A dose of 4 X 10(9) colony-forming units of strain BC181, serotype 3, induced pulmonary necrosis similar to the lesions in pigs given 10(7) colony-forming units or less of strain W, serotype 1, suggesting that the serotype 3 strain is less virulent. No clinical signs, but focal areas of pulmonary fibrosis and pleural adhesions were induced in four pigs inoculated with 4 X 10(9) colony-forming units of the "minor-group" strain 7ATS. Similarly, four pigs inoculated with "minor-group" strain 33PN did not show clinical signs, but had focal necrotic and fibrotic pulmonary lesions and pleural adhesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗