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211.
Partial characterization of a turkey enterovirus-like virus. 总被引:1,自引:0,他引:1
Small round viruses, 18 to 24 nm in diameter, were detected by electron microscopy in droppings of young turkeys with enteritis. The virus was propagated in embryonated turkey eggs and tentatively identified as an enterovirus based on size, intracytoplasmic morphogenesis, buoyant density of 1.33 g/ml in CsCl, and a single-stranded RNA genome of approximately 7.5 kb. It was distinguished from avian encephalomyelitis virus by cross-immunofluorescence. These results identify an enterovirus-like virus as a possible etiologic agent of enteric disease of young turkeys. However, its role in this disease remains to be established. 相似文献
212.
Experimental production of bovine respiratory tract disease with bovine viral diarrhea virus 总被引:10,自引:0,他引:10
L N Potgieter M D McCracken F M Hopkins R D Walker J S Guy 《American journal of veterinary research》1984,45(8):1582-1585
Five 6-month-old calves were inoculated with bovine viral diarrhea (BVD) virus (n = 3) or Pasteurella haemolytica (n = 2) endobronchially with a fiberoptic bronchoscope. Five additional calves were inoculated sequentially with BVD virus followed by P haemolytica at a 5-day interval. Blood samples were collected daily from the calves for bacterial isolation. Clinical signs of respiratory tract disease in calves were recorded daily. If the calves survived, they were killed for necropsy 3 or 4 days after inoculation with P haemolytica (or 8 days after inoculation with BVD virus). The extent and nature of pulmonary lesions in the calves were determined, and the lower portion of the respiratory tract (lungs and trachea) was examined for both these organisms. The 3 calves, inoculated with BVD virus only, developed mild clinical signs mainly manifested as fever, nasal discharge, and occasional cough. Approximately 2% to 7% of the total lung capacity of these calves was pneumonic. Mild clinical signs and localized lesions involving about 15% of the lung volume developed in the 2 calves exposed to P haemolytica only. However, severe fibrinopurulent bronchopneumonia and pleuritis involving 40% to 75% of lung volume developed in the 5 calves inoculated sequentially with BVD virus and P haemolytica. The possible role BVD virus may have in bovine respiratory tract disease is discussed. 相似文献
213.
Fradette ME Céleste C Richard H Beauchamp G Laverty S 《American journal of veterinary research》2007,68(2):128-133
OBJECTIVE: To evaluate the effects of continuous oral administration of phenylbutazone on serum and synovial fluid biomarkers of skeletal matrix metabolism in horses. ANIMALS: 11 adult female horses without clinical or radiographic evidence of joint disease. PROCEDURES: Horses were randomly assigned to control or treatment groups. Phenylbutazone was administered orally twice daily at a dose of 4.4 mg/kg for 3 days to the treatment group and subsequently at a dose of 2.2 mg/kg for 7 days. Serum and radiocarpal synovial fluid samples were obtained at baseline and thereafter at regular intervals for 4 weeks. Biomarkers of cartilage aggrecan synthesis (chondroitin sulfate 846) and type II collagen synthesis (procollagen type II C-propeptide) and degradation (collagen type II cleavage) were assayed. Biomarkers of bone synthesis (osteocalcin) and resorption (C-terminal telopeptide of type I collagen) were also measured. RESULTS: No significant differences were found between control and treatment groups or temporally for the biomarkers chondroitin sulfate 846, procollagen type II C-propeptide, collagen type II cleavage, and C-terminal telopeptide of type I collagen in serum or synovial fluid. A significant increase in osteocalcin concentration occurred in synovial fluid during treatment in the treated group. No treatment effect was detected for serum osteocalcin concentration. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that continuous phenylbutazone administration at recommended doses altered some biomarkers in healthy equine joints after short periods of administration. Increased osteocalcin concentration may indicate an undetermined anabolic effect of phenylbutazone administration on periarticular bone or transient induction of osteogenesis in articular chondrocytes or a mesenchymal subpopulation of synoviocytes. 相似文献
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