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41.
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   
42.
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   
43.
Two experiments were done on 57 steers. These cattle were allotted to 8 groups (4 groups/experiment) and vaccinated with 1 to 3 X 10(9) colony-forming units of Brucella abortus strain 19. Cattle in 3 of the 4 groups/experiment were given 6 mg of levamisole/kg, subcutaneously, either at the time of vaccination (day 0), 7 days later, or at both times. Serum antibody titers to B abortus were measured sequentially for 28 days in experiment 1 and for 56 days in experiment 2, using the card test, Rivanol test, complement-fixation test, fluorometric immunoassay, and an enzyme-linked immunosorbent assay. In general, the highest mean antibody titers, as determined by all serologic tests, occurred in steers treated with levamisole at 7 days after vaccination or in those treated at the time of vaccination and 7 days later. By the card test on day 56, there was a significantly (P less than 0.05) greater number of seropositive cattle among those given levamisole 7 days after seropositive cattle among those given strain 19 alone. Simultaneous administration of strain 19 and levamisole did not alter antibody responses to B abortus.  相似文献   
44.
Cutaneous cryptococcosis in three cats   总被引:1,自引:0,他引:1  
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   
45.
46.
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   
47.
48.
Two dogs developed a generalised bleeding disorder after ingestion of brodifacoum, a compound belonging to a new generation of more potent and longer-acting anticoagulant rodenti-cides. Haemorrhage recurred after treatment with conventional dosages of vitamin K1 Successful therapy required dosages of vitamin K1 of 5 mg/kg for a period of up to eight weeks.  相似文献   
49.
A procedure is described for isolating Eperythrozoon suis DNA of sufficient quantity and purity to serve as a probe in whole-organism DNA hybridizations for detecting parasitized swine. The E. suis organisms were isolated from the blood of infected swine; the DNA was recovered and digested with restriction endonucleases and resolved on agarose gels. In DNA hybridizations using recovered E. suis DNA, blood samples from parasitized swine could be differentiated from uninfected, control samples. A high salt lysate recovery technique was used in sampling swine whole blood for E. suis DNA and found to offer many advantages in the collection and recovery process.  相似文献   
50.
A questionnaire survey of the prevalence of scrapie in sheep in Britain   总被引:2,自引:0,他引:2  
An anonymous, self-administered questionnaire has been used in two independent surveys to try to determine the prevalence of scrapie in the national sheep flock. The disease was recorded in 35 counties in England and Wales. About a third (26.5 and 37.3 percent) of respondents owning 100 or more sheep indicated that they had seen sheep with scrapie in their flocks. The incidences of clinical cases recorded in affected flocks in the two surveys were 0.5 and 1.1 cases/100 ewes/year. At present there is no control over the disposal of these animals. If as has been suggested, an increase in the prevalence of scrapie was a contributory factor in the emergence of bovine spongiform encephalopathy, it would seem logical that measures should be introduced to monitor the prevalence and incidence of scrapie and to control the disposal of clinical cases.  相似文献   
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