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41.
42.
Productivity data were gathered from Mashona cows (n = 187) in 28 traditionally managed herds in two areas, separated by a corridor 20–30 km wide of almost uninhabited bush in NE Zimbabwe. Cattle are kept primarily to provide oxen for work. Cows in the southern area, which had been more affected by drought in 1991–92, were younger (7.2 vs. 9.1 years) and had a longer median calving interval (548 vs. 406 days). Metrical data (n = 105 cows) showed these cattle to be larger-bodied than those in the northern area (heart girth 146 vs. 144 cm). Market prices, estimated by respondents, were higher for oxen and herds were smaller in the south, and calf survival was believed by owners to be more influenced by season of birth in this area. Data were obtained on 531 calves. Before the age of 12 months 6.2% died, a low proportion compared with other studies. Most were retained in herds but 11.5% were slaughtered, sold or given away. All owners practised castration, selecting fast growing, strong bull calves for breeding. 相似文献
43.
A J Hall 《Journal of zoo and wildlife medicine》1998,29(4):401-407
Serum and plasma samples were collected from 92 gray seal (Halichoerus grypus) pups, all less than 5 wk old, and from 21 yearlings during the breeding season at the Isle of May, Firth of Forth, Scotland, for hematologic and clinical chemistry analysis. In the pups, total WBC, total protein, and glucose values increased until weaning and declined during the postweaning fast. Liver enzymes, particularly alkaline phosphatase, were high at birth and decreased steadily with age, most rapidly during the postweaning fast. In the yearlings, total WBC, erythrocyte sedimentation rates, and rectal temperatures were significantly higher than in the pups and glucose levels were significantly lower. Therefore, consideration should be given to the growth phase of gray seal pups (lactation or postweaning fast) or stage of development when hematology and clinical chemistries are used for diagnostic purposes. 相似文献
44.
Seven wild-caught ball pythons (Python regius), including six gravid females and one male, were obtained from Africa and were housed in a government animal facility in Research Triangle Park, North Carolina. Upon arrival, the snakes were found to be infested with ticks (Aponomma latus), which were manually removed. Four weeks following arrival, vesicular skin lesions began to appear on the snakes. Despite treatment of all affected female snakes with amikacin (5 mg/kg i.m., every 3 days) and cefotaxime (25 mg/kg i.m., every 3 days), the condition progressed and five of the female snakes died 7 wk after arrival. The remaining male and one female improved after an increase in environmental temperature, with ecdysis followed by healing. Physiologic stress, ectoparasites, and shipping may have predisposed the snakes to sepsis. 相似文献
45.
H.W. Brooks G.A. Hall A.J. Wagstaff A.R. Michell 《Veterinary journal (London, England : 1997)》1998,155(3):263-274
This paper examines the possibility that treatment of diarrhoea with conventional oral rehydration solutions (ORSs) may be detrimental to villus structure by imposing nutrient deprivation and that such detrimental effects may be reduced or avoided by using a nutrient ORS. A conventional WHO-type ORS (W) was compared with two nutrient solutions (N and G) both containing high glucose concentrations and the latter containing glutamine; their effects on enteric structure were assessed by morphometric analysis of samples obtained from diarrhoeic calves after 96h treatment. Comparisons were also made with samples from controls and diarrhoeic calves at the stage where oral rehydration would have begun in the treated groups. As in our previous ORS studies, diarrhoea was induced with enterotoxigenic Escherichia coli (09:K30:K99). We measured villus length and width, crypt depth and width and calculated villus surface area in proximal, mid and distal small intestine (PSI, MSI, DSI), using standard morphometric techniques. Proximal and distal spiral colon samples (PC, DC) were examined for crypt depth and width; mitoses per crypt were counted in samples from all regions. Non-diarrhoeic calves showed the expected gradient of villus length through PSI, MSI and DSI, hence data for each region are normalized as a percentage of the control value for that region. PSI showed the greatest loss of villus length and surface area (50%) with diarrhoea. In MSI and DSI the villus loss was greater with solution W and N or G, as were increased mitoses and crypt depth. Crypt depth and mitoses also increased in the colon with solution W. Colonic crypt width increased with diarrhoea and conventional oral rehydration but less so with G; there is reason to believe that such changes have functional significance. Crypt changes in colon, MSI and DSI were least with solution G. The changes developing in diarrhoeic calves prior to treatment were thus less apparent in those treated with a nutritional ORS, particularly if it contained glutamine. 相似文献
46.
Abstract— Juvenile Penaeus monodon prawns were exposed to a variety of putative stressom and blood glucose concentrations monitored as an index of metabolic stress. Prawns were held under controlled conditions and food deprived for 12–18 h before blood sampling. Juvenile prawns maintained in tanks at densities of 9, 23, 36 and 50 prawns/m2 for 4 wk did not have significantly different baseline levels of blood glucose, with mean concentrations varying from 1.1 to 1.3 mmol/L. In contrast, as an index of overall condition, antennal length and rostral spine length were significantly degraded in the 36 and 50 prawns/m2 groups compared to the 9 and 23 prawns/m2 groups ( P < 0.05). Blood glucose levels were significantly elevated after prawns were exposed to air for 10 min and also increased Significantly when dissolved oxygen was decreased from 6.5 mg/L to 2.1 mg/L. ( P < 0.05). Gassing of water from pH 8.5 to 5.9 with carbon dioxide, with a corresponding decrease of dissolved oxygen from 6.6 to 5.9 mg/ L, induced a rapid and significant rise in blood glucose levels from 1.1 to 2.3 mmol/L. In contrast, a decrease of water pH from 8.3 to 5.9 with sulfuric acid, did not result in a significant change in blood glucose concentrations. These findings are discussed in relation to pond management for maintaining prawns in a low stress environment. 相似文献
47.
Cutaneous cryptococcosis in three cats 总被引:1,自引:0,他引:1
L Medleau E J Hall M H Goldschmidt N Irby 《Journal of the American Veterinary Medical Association》1985,187(2):169-170
Cutaneous cryptococcosis was diagnosed in 3 cats. No other organ involvement was found. One cat has remained healthy after surgical excision of the cryptococcal skin lesion. One cat was euthanatized after diagnosis. The third cat was treated successfully with a 5-month course of ketoconazole. 相似文献
48.
49.
Plasma enteroglucagon and neurotensin levels in gnotobiotic calves infected with enteropathogenic and non-enteropathogenic viruses 总被引:1,自引:0,他引:1
G A Hall K R Parsons J C Bridger M A Ghatei Y C Ying S R Bloom 《Research in veterinary science》1985,38(1):99-103
Five gnotobiotic calves were each infected with five viruses. Each calf was inoculated with coronavirus at seven days old, followed by astrovirus, Newbury agent, parainfluenzavirus type 3 and rotavirus at intervals of two weeks. Three of the viruses were enteropathogenic (bovine coronavirus, bovine calici-like virus and bovine rotavirus) and two were not (bovine astrovirus and parainfluenzavirus type 3). Plasma levels of the peptide hormones enteroglucagon and neurotensin and faecal output were measured daily and xylose absorption was studied before and after each infection. A close correlation was found between a rise in plasma enteroglucagon and neurotensin and infection with enteropathogenic viruses. The three enteropathogenic viruses caused increased daily faecal output, and elevated plasma levels of enteroglucagon and neurotensin, while the non-enteropathogens did not. The calici-like virus and rotavirus but not the coronavirus caused xylose malabsorption. 相似文献
50.