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941.
The serological responses of calves at two different ages to a commercial hardjo/pomona vaccine were examined. Microscopic agglutination test (MAT) titres of a group of ten three-month-old calves and three groups of 11,12 and 12 six-month-old calves were monitored over a period of 28 weeks. The calves vaccinated at three months of age had a poorer serological response rate to vaccination (30% responded to pomona and 40% responded to hardjo) compared with those vaccinated at six months of age (91-100% responded to pomona and 83-91% responded to hardjo). Those three-month-old calves which did respond also produced a lower level of-antibody than six-month-old calves. It was concluded that in order to achieve adequate protection using commercially available leptospiral bacterins at the recommended dose, vaccination should not be undertaken routinely with animals less than six months of age. Where circumstances arise in which earlier vaccination is necessary, repeat vaccination for continued protection at six months or older is suggested.  相似文献   
942.
943.
Lytic lesions occurring in conjunction with plasma cell sarcoma (multiple myeloma) have rarely been reported in cats.

A plasma cell sarcoma was diagnosed in a 13 year old castrated male Siamese cat with hind limb paresis resulting from osteolysis of the second lumbar vertebra. Serum electrophoresis showed a monoclonal gammopathy. A uniform population of plasma cells was found in and around the second lumbar vertebra and in the bone marrow of the femora, humeri, pelvis and the fifth lumbar vertebra. The neoplastic cells were identified as IgA and kappa chain specific by direct immunofluorescence.

  相似文献   
944.
945.
Infection with Fascioloides magna, the large American liver fluke, was diagnosed in two moose (Alces alces) and six wapiti (Cervus elaphus) from central Saskatchewan. This is believed to be the first record of the parasite in the province. Fecal samples collected from wild wapiti at five sites in the commercial forest zone in Saskatchewan contained eggs believed to be those of F. magna. Trematode eggs were not found in feces from five captive herds of wapiti in the province, nor in samples from wild wapiti in Moose Mountain Provincial Park. Operculate eggs were found in feces of wild wapiti from Cypress Hills, but these were believed to be from trematodes other than F. magna. The distribution and significance of F. magna in Canada, based partially on responses to a mail questionnaire, are reviewed.  相似文献   
946.
A developmental anomaly, resulting from partial segmental aplasia of the Mullerian ducts, was present in a Clydesdale mare. She had complete double cervices and a divided uterine body. In this mare, bilateral pregnancies were destroyed in sequence by squeezing them per rectum 25 and 29 days after insemination.  相似文献   
947.
The temporary dentitions of 18 to 39-week-old lambs with a very light or a very heavy parasite burden are compared. The heavily parasitised lambs developed longer temporary incisors which tended to protrude further forward in relation to the upper dental pad. They showed absolute hypocalcaemia and hypoalbuminaemia and relative hypophosphataemia and hypoproteinaemia and in the alveolar bone of the mandible there was a reduction in ash and matrix densities and matrix mineralisation. The incisor protrusion and lengthening may have been a consequence of the loss of supporting bone, but inappetance was likely to have been a factor contributing to the lengthening.  相似文献   
948.
949.
An outbreak of leptospirosis due to Leptospira interrogans serovar hardjo in the South Okanagan District of British Columbia was investigated. The infection was associated primarily with bulls, but serovar hardjo was isolated from both bulls and cows at slaughter. Kidney and cerebrospinal fluid were found to contain leptospires, independently of the presence and level of serum agglutinins. Treatment of a bull twice in six months with dihydrostreptomycin failed to diminish an agglutinin titer (1/200) which persisted for two years without reexposure of the bull. A serological survey of cull cows sold through a central auction mart revealed the presence of hardjo agglutinins in 15.4% of 1300 sera representing 163 herds in 20 locations. Thirty percent of these herds contained reactor cattle. The number of premises from which reactor cattle came in a given locality varied from 4% to 67.7%. Measures to control leptospirosis in the study are suggested.  相似文献   
950.
A transitional cell carcinoma of the urinary bladder was found in a beluga whale stranded in the St. Lawrence middle estuary. Various organs of this animal were submitted to high resolution gas chromatography coupled with mass spectrometry analysis. High frequency of urinary bladder cancer in the human population of the same area and the presence of carcinogenic compounds in the marine environment of this animal are discussed.

Concurrent isolation of Edwardsiella tarda from various organs of this whale is also reported.

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