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排序方式: 共有439条查询结果,搜索用时 15 毫秒
51.
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Colonic adenocarcinoma with osseous metaplasia in a horse 总被引:1,自引:0,他引:1
J B Rottman M C Roberts J M Cullen 《Journal of the American Veterinary Medical Association》1991,198(4):657-659
Rectal palpation of a 30-year-old mixed-breed mare with chronic weight loss and intermittent, refractory abdominal pain revealed a mass in the right caudoventral portion of the abdomen. Hematologic and serum biochemical findings were normal except for slight mature neutrophilia and mildly high alkaline phosphatase activity and total bilirubin concentration. Cytologic examination of a specimen obtained by abdominocentesis revealed equal numbers of nondegenerative neutrophils and macrophages, but no evidence of neoplastic cells. The mare continued to have signs of abdominal discomfort and was euthanatized. Necropsy revealed a large mass at the junction of the right dorsal colon and transverse colon, and several smaller masses in the liver. Histologic characteristics of the small-colon mass were consistent with colonic adenocarcinoma with osseous metaplasia. 相似文献
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Serological response of turkey hens to vaccination with Salmonella hadar and its effect on their subsequently challenged embryos and poults 总被引:1,自引:0,他引:1
An inactivated Salmonella hadar vaccine was administered to parent turkey stock and the progeny were subjected to challenge with S hadar. There was some evidence that eggs from vaccinated birds were more resistant to growth of the organism. When compared with similarly infected poults from unvaccinated parents, a markedly different serological picture and pattern of salmonella excretion was seen. It appeared that the passive immunity induced by the vaccine encouraged the faster establishment of other gut Enterobacteriacae, even in the presence of large numbers of S hadar. 相似文献
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Six animals were used to compare simple interrupted, simple continuous, and stapled techniques for end-to-end rotated small colon anastomoses. Three ponies were evaluated three days after surgery for adhesion formation and luminal diameter at each anastomosis site. Two ponies and one horse were evaluated 14 days after surgery for adhesion formation. All anastomosis sites were examined histologically for alignment of tissue planes, and evidence of inflammation. No single technique was superior in all areas examined. While only three of the nine anastomoses had mild fibrinous adhesions at three days after surgery, all anastomoses had varying degrees of well-organized adhesions by 14 days after surgery. Three days after surgery luminal diameter was most comprised by the simple continuous technique. Although the simple interrupted technique was most consistent in its alignment of tissue planes, it was only slightly better than the simple continuous pattern. Stapled anastomoses were inverted or everted at all sites examined. Adhesion formation was less extensive, and histologic evidence of inflammation was less severe, in stapled anastomoses. The average times required to complete the simple interrupted, simple continuous, and stapled anastomoses were 22, 14, and 8 minutes, respectively. 相似文献
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PJ CHENOWETH 《Australian veterinary journal》1994,71(12):422-426
SUMMARY Differences occur between female Bos indicus and Bos taurus cattle in various aspects of reproductive physiology and behaviour. These may be associated with different natural and human selection pressures, compounded by strong genotype-environment interactions. B indicus cattle are better adapted for tropical environments (despite overall poor cattle reproductive rates in these regions) which tend to be more stressful for B taurus genotypes. Conversely, B taurus cattle generally show superior reproductive and productive traits under more favoured, temperate conditions. Despite genotype-environment effects, B indicus females are generally considered to take longer to achieve puberty and to have longer gestation lengths, exhibit prolonged postpartum anoestrus, show greater seasonality of reproductive traits (tending to be long-day breeders), display a shorter, less overt oestrus as well as less tendency to allow riding behaviour by subordinate females. Some groups appear to have increased losses both during pregnancy and in the neonatal period. On the positive side, B indicus females respond well to managerial and nutritional interventions, tend to have greater reproductive longevity and they generally exhibit strong maternal traits. Culling of infertile females and selection for greater male scrotal circumference and sex-drive, in conjunction with the use of target weights, body condition scoring and weaning stratagems can improve reproductive rates in B indicus females. 相似文献
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J M Cullen M Wilson W M Hagler J F Ort R J Cole 《American journal of veterinary research》1988,49(5):728-731
Cyclopiazonic acid dissolved in corn oil was administered by gavage to broiler chicks (n = 80) daily, from the day of hatching for 23 days. Chicks were assigned to 3 groups (1, 2, or 4 mg of cyclopiazonic acid/kg of body weight); a control group was given corn oil. Each group was composed of 10 male and 10 female chicks. Surviving chicks were euthanatized and necropsied on day 24. Histologic examination revealed that the most common lesions consisted of necrosis and hemorrhage or hyperplasia of the mucosa of the proventriculus and hepatocellular vacuolation. Skeletal muscle degeneration, characterized by myofiber swelling or fragmentation accompanied by an infiltrate of macrophages and heterophils, was detected in the group given 4 mg/kg. This degeneration was associated with an increase of plasma creatine kinase activity. Focal hepatocellular and splenic necrosis also developed in the groups given 4 mg/kg. 相似文献