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排序方式: 共有194条查询结果,搜索用时 15 毫秒
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SUMMARY The analysis of records for 75 821 herd tests on 23 700 cows in the Macalister Irrigation District of East Gippsland, using a model that also included stage of lactation, herd and cow effects, found a strong relationship between somatic cell count and milk production. Unit increases in the natural logarithm of the somatic cell count were associated with decreases in production of up to 2.6% in the range 54 598 to 403 429 cells per mL. This is equivalent to a decrease of 1.9% for a doubling of cell count from 100 000 to 200 000 cells per mL. Subclinical mastitis was assessed to be a significant source of loss in milk production in the study area. 相似文献
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GA SMITH PL YOUNG† BJ RODWELL† MA KELLY† GJ STORIE† CA FARRAH† JS MATTICK† 《Australian veterinary journal》1994,71(3):65-70
SUMMARY An Australian bovine herpesvirus 1 (BHV1) isolate with a defined (427 base pair) deletion in the protein coding region of the thymidine kinase gene was obtained by standard marker rescue procedures. After selection in the presence of the nucleotide analogue 5iodo-deoxy-uridine the virus was analysed by hybridisation with three differential oligonucleotide probes, restriction endonuclease profile studies and DNA sequence analysis. The virus elicited an immune response in recipient animals after either intramuscular or intravenous administration and produced no significant deleterious side-effects when administered at a dose sufficient to stimulate the host immune response. The safety and immunogenicity of the recombinant BHV1 virus 39B1 were similar to those reported for other registered BHV1 vaccines and the virus would appear to be suitable for the production of a vaccine seed lot and more exhaustive field trials as a prelude to commercial vaccine production and registration. 相似文献
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Nathan L. Dykes DVM Lorin D. Warnick DVM Brian A. Summers BVSc MSc PhD Robert J. Wallace BS Francis A. Kallfelz DVM PhD 《Veterinary radiology & ultrasound》1994,35(1):59-65
We performed a retrospective study of 100 dogs and 16 cats with planar brain scintigraphy and histopathologically established diagnoses from a total of 485 studies performed from 1976 to 1992. Necropsy (112) or surgical biopsies (4) diagnoses were categorized in two ways: first as focal brain disease, diffuse brain disease or normal; second as either neoplastic, non-neoplastic or normal. A radiologist reviewed brain scintigrams and categorized the studies as focal areas of increased accumulation, diffuse or poorly localized areas of increased accumulation, or normal. We calculated for this population of 116 animals that focal brain scintigrams had 75% sensitivity and 90% specificity for any focal brain disease. The sensitivity and specificity of a focal scintigraphic lesion for a brain tumor was 72% and 82% respectively. The sensitivity and specificity of a diffuse or poorly localized scintigraphic lesion as a test for diffuse brain disease was 40% and 88% respectively. 相似文献
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Todhunter RJ Grohn YT Bliss SP Wilfand A Williams AJ Vernier-Singer M Burton-Wurster NI Dykes NL Wu R Casella G Acland GM Lust G 《American journal of veterinary research》2003,64(12):1472-1478
OBJECTIVE: To determine the radiographic methods that best predict the development of osteoarthritis in the hip joints of a cohort of dogs with hip dysplasia and unaffected dogs. ANIMALS: 205 Labrador Retrievers, Greyhounds, and Labrador Retriever-Greyhound crossbred dogs. PROCEDURE: Pelvic radiography was performed when the dogs were 8 months old. Ventrodorsal extended-hip, distraction, and dorsolateral subluxation (DLS) radiographs were obtained. An Orthopedic Foundation for Animals-like hip score, distraction index, dorsolateral subluxation score, and Norberg angle were derived from examination of radiographs. Osteoarthritis was diagnosed at the time of necropsy in dogs > or = 8 months of age on the basis of detection of articular cartilage lesions. Multiple logistic regression was used to determine the radiographic technique or techniques that best predicted development of osteoarthritis. RESULTS: A combination of 2 radiographic methods was better than any single method in predicting a cartilage lesion or a normal joint, but adding a third radiographic method did not improve that prediction. A combination of the DLS score and Norberg angle best predicted osteoarthritis of the hip joint or an unaffected hip joint. All models that excluded the DLS score were inferior to those that included it. CONCLUSIONS AND CLINICAL RELEVANCE: A combination of the DLS score and Norberg angle was the best predictor of radiographic measures in 8-month-old dogs to determine whether a dog would have normal or osteoarthritic hip joints. 相似文献
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SUMMARY: Psittacine beak and feather disease virus (PBFDV) was administered to adult galahs ( Eolophusroselcapillus ) by mouth or by intramuscular injection. Concentration of PBFDV antibodies in serum and excretion of PBFDV were monitored by haemagglutlnation inhibition (HI) and haemagglutination (HA) respectively. After oral administration, 17 of 18 galahs remained clinically normal and a small rise in antibody titre was detected in 3 of 18 birds. After intramuscular administration, antibody was detected in all birds. PBFDV was not detected in the feather dander of birds in either group. One bird developed diarrhoea and high faecal HA titres within 4 days of oral administration and then died. Adult and nestling cockatoos were vaccinated with an experimental inactivated double-oil emulsion vaccine. PBFDV antibody responses are comparable to those induced by a primary-oil emulsion vaccination regimen using Freund's adjuvants. Both vaccines protected nestlings. Three sibling wild-caught sulphur-crested cockatoos were vaccinated but died of PBFD before experimental challenge despite antibody responses in all birds. Unvaccinated control chicks developed acute PBFD within 4 weeks of challenge, probably from PBFDV-induced hepatitis since high concentrations of PBFDV were detected in their livers. 相似文献
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