The indirect hemagglutination test for the detection of antibodies in cattle naturally infected mycoplasmas.
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Stable mycoplasma antigens for the indirect hemagglutination test (IHA) were prepared employing glutaraldehyde treated sheep erythrocytes sensitized with Mycoplasma agalactiae subsp. bovis and Mycoplasma bovigenitalium antigens. Employing these antigens mycoplasma antibodies were detected in sera from cattle which had mastitic symptoms due to natural infection with either M. agalactiae subsp. bovis or M. bovigenitalium. A total of 200 cows from four herds were examined at varying intervals for the presence of M. agalactiae subsp. bovis and for the detection of antibody using growth inhibition and IHA tests. Mycoplasmas were isolated from 37 animals. Growth inhibiting antibody was detected from 56 of the 200 animals. In the IHA tests, antibody titer greater than or equal to 1:80 were detected in 148 animals, 76 of these having antibody titers greater than or equal to 1:160, while sera of 116 normal control animals had no growth inhibiting antibody and none had IHA antibody titers greater than 1:40. M. bovigenitalium was isolated from the milk of three of 26 animals in a fifth herd during an outbreak of mastitis. Growth inhibiting antibodies were demonstrated in the sera of ten of the 26 animals. However, the IHA test detected antibody titers of greater than or equal to 1:160 in 13 animals and of 1:80 in one of the 26 animals. To determine the specificity of the IHA tests, M. agalactiae subsp. bovis and M. bovigenitalium antigens were reacted with rabbit hyperimmune typing sera produced against 12 species of bovine mycoplasmatales. Homologous antisera showed IHA antibody titers of 1:1280 and 1:2560 against M. agalactiae subsp. bovis and M. bovigenitalium respectively, whereas heterologous antisera showed IHA antibody titers of less than or equal to 1:20. Also eight type-specific bovine antisera were reacted with M agalactiae subsp. bovis and M. bovigenitalium antigens in homologous and heterologous tests. Homoogous reactions showed IHA antibody titers greater than or equal to 1:320, whereas heterologous reactions showed IHA titers of less than or equal to 1:20. This IHA test promises to be useful for the detection of bovine mycoplasma antibodies in sera from cattle infected with M. agalactiae subsp. bovis or M. bovigenitalium. Thes test is sensitive, reproducible and specific and the technique is relatively simple and rapid. The antigens were stable for at least seven months. (+info)
Bovine mastitis in Ontario due to Mycoplasma agalactiae subsp. bovis.
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Bovine mastitis caused by Mycoplasma agalactiae subsp. bovis was first diagnosed in 16 of 55 cows in an Ontario herd in Feburary 1972. A total of 182 of 598 (30.4%) cows from 33 of 64 (51.5%) farms in widely separated areas of the province were culturally positive. Herd incidence varied from 15 to 40% with one closed herd having an incidence of 61%. Four herds were investigated culturally and serologically by the growth inhibition test for 15 months. In the acute phase the organism was present in the milk in extremely high numbers and could still be isolated from a few cows after eight to 12 months. The sera from 89.5% of the animals with clinical mycoplasma mastitis produced a zone of surface "film" and/or colony inhibition and some cows remained positive for six to 12 months. The disease was experimentally reproduced with a pure culture of the organism isolated from the milk of a cow from one of the herds. (+info)
Identification of nonlipophilic corynebacteria isolated from dairy cows with mastitis.
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Nonlipophilic corynebacteria associated with clinical and subclinical mastitis in dairy cows were found to belong to four species: Corynebacterium amycolatum, Corynebacterium ulcerans, Corynebacterium pseudotuberculosis, and Corynebacterium minutissimum. These species may easily be confused. However, clear-cut differences between C. ulcerans and C. pseudotuberculosis were found in their acid production from maltotriose and ethylene glycol, susceptibility to vibriostatic agent O129, and alkaline phosphatase. Absence of growth at 20 degrees C and lack of alpha-glucosidase and 4MU-alpha-D-glycoside hydrolysis activity differentiated C. amycolatum from C. pseudotuberculosis and C. ulcerans. The mastitis C. pseudotuberculosis strains differed from the biovar equi and ovis reference strains and from caprine field strains in their colony morphologies and in their reduced inhibitory activity on staphylococcal beta-hemolysin. C. amycolatum was the most frequently isolated nonlipophilic corynebacterium. (+info)
Molecular analysis of Pseudomonas aeruginosa: epidemiological investigation of mastitis outbreaks in Irish dairy herds.
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Pseudomonas aeruginosa is a pathogen in both humans and animals. This bacterium, most often associated with respiratory infections in cystic fibrosis patients, was found to be the causative agent in bovine mastitis outbreaks among 11 Irish dairy herds. Epidemiological findings suggested that the infection was spread to all herds by teat wipes that had been contaminated with this organism. Two molecular-typing strategies were used in an attempt to determine the genomic relationship(s), if any, of the P. aeruginosa strains isolated from the various herds and to verify whether the same strain was responsible for each outbreak. Thirty-six isolates from the mastitis outbreaks were tested and compared to fourteen clinical isolates from Cork University Hospital. With one exception, all outbreak-linked strains produced identical patterns when ribotyped with ClaI and PvuII enzymes. Eight of the clinical isolates gave the same ClaI ribotype pattern as the mastitis-causing strains. However, PvuII proved more discriminatory, with only the outbreak isolates producing identical patterns. Similar results were obtained with RW3A-primed DNA amplification fingerprinting, with all outbreak isolates except one displaying the same fingerprint array. The clinical strains produced several fingerprint patterns, all of which were different from those of the mastitis-causing isolates. Fine-resolution DNA fingerprinting with a fluorescence-labelled RW3A primer also identified a number of low-molecular-weight polymorphisms that would have remained undetected by conventional methods. These data support the view that the same P. aeruginosa strain was responsible for the mastitis outbreaks in all 11 herds. (+info)
Coagulase gene polymorphism of Staphylococcus aureus isolates from dairy cattle in different geographical areas.
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The objectives of this study were to investigate the coagulase gene polymorphism of Staphylococcus aureus isolates obtained from bovine mastitic milk and to determine the resistance of predominant and rare coagulase genotypes to bovine blood neutrophil bactericidal activities. A total of 453 isolates were collected from four countries: the Czech Republic, France, Korea and the United States. The isolates were subtyped into 40 types by restriction fragment length polymorphism (RFLP) of the coagulase gene. Twenty-three strains from predominant and rare genotypes were evaluated for their ability to resist neutrophil bactericidal activities. There were significant (P < 0.01) differences in the average percent neutrophil killing of the predominant (16.7%) and rare (39.7%) genotypes when bacteria were opsonized with antiserum. The results indicate that the profiles of coagulase genotype differ among geographic locations, and only a few genotypes prevail in each location. In addition, the predominant genotypes were more resistant to neutrophil bactericidal activities than rare genotypes. (+info)
Effect of vitamin B2 on somatic cell counts in milk of clinical Staphylococcus aureus mastitis.
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Effects of intravenous injection of Vitamin B2 (VB2) on the nitroblue tetrazolium (NBT) reductivity of peripheral blood neutrophils and the somatic cell counts (SCC) in quarter milk of Staphylococcus aureus mastitis were investigated. The NBT reductivities of neutrophils were enhanced at 2 days after single injection of VB2 (5.0 and 2.5 mg/kg), and were also enhanced at 4 days after initial injection of continuous 3 days of VB2 (2.5 mg/kg). The SCC in quarter milk were significantly decreased at 3, 7 and 14 days after initial injection of continuous 3 days of VB2 (2.5 mg/kg), however, S. aureus in the infected quarter was not cured bacteriologically by VB2 injection. (+info)
Streptococcus pluranimalium sp. nov., from cattle and other animals.
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Strains from subclinical mastitis, from the genital tract and tonsils of cattle, from tonsils of a goat and a cat and from the crop and the respiratory tract of canaries were found to constitute a new streptococcal species, for which the name Streptococcus pluranimalium sp. nov. is proposed. Sequencing of 16S rRNA showed that Streptococcus thoraltensis and Streptococcus hyovaginalis were its closest known phylogenetic relatives. The new species showed some phenotypic resemblance to the poorly described species Streptococcus acidominimus, but whole-cell protein analysis and 16S rRNA sequencing revealed that the new species was only distantly related to the type strain of S. acidominimus. Identification of these bacteria, which showed heterogeneous biochemical reaction patterns, was most reliably made by whole-cell protein analysis. Nevertheless, a number of biochemical reactions can be used to differentiate S. pluranimalium from other animal streptococci. Strain LMG 14177T, isolated from mastitic milk of a dairy cow, was designated as the type strain of S. pluranimalium sp. nov. (+info)
An epidemiologic study of disease in 32 registered Holstein dairy herds in British Columbia.
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Data recorded in a herd health management system were obtained from 32 registered Holstein dairy herds from British Columbia. Frequencies of disease were described, and the effect of herd, age, year, season, and the interrelationships between diseases within a lactation on the occurrence of disease were evaluated. Lactational incidence rates were computed for diseases with a short period of risk (ie, udder edema, milk fever, retained placenta, metritis, displaced abomasum, and ketosis), whereas for diseases with a longer period of risk (ie, cystic ovaries, mastitis and stable footrot), incidence densities were calculated. Overall, the disease incidence was low and showed an increase in frequency by year, which we attributed to more observing and complete recording by the owner, rather than an actual increase in disease incidence. Most diseases occurred early in lactation and their frequency increased with lactation number; the exception was udder edema, which occurred mainly during the first 2 lactations. An informal path model of disease interrelationships was made conditional on herd. Based on the results we inferred 2 independent pathways: one started by udder edema, and the other by milk fever. Udder edema was directly associated with mastitis occurrence from 0 to 30 d in lactation, metritis, and cystic ovaries. Mastitis from 0-30 d in lactation increased the risk of both mastitis from 31-150 d in lactation and cystic ovaries. Both of these increased the risk of late lactation mastitis. Milk fever was directly related with displaced abomasum, which increased the risk of footrot. In general, diseases that occurred in early lactation tended to increase the risk of other diseases later in lactation. (+info)