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Six horses, which had a foreign body obstruction of the small colon showed abdominal pain of progressing severity and intestinal tympany. On rectal examination the caecum and large colon were distended with ingesta and gas but the obstructing mass could be palpated in only 3 cases. All horses had elevated indirect blood pressure and in 3 there was also fluid distension of the stomach. Only one horse had known access to foreign material in the diet, but a further 3 were related to an exceptionally dry climate period. Five of the 6 horses recovered following surgery. 相似文献
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B.W. Parry BVSc PhD B.A. Christie BVSc MACVSc C.C. Gay DVM MVSc FACVSc R.N. Haywood BVSc 《Journal of Equine Veterinary Science》1983,3(1):24-27
A case of acute circulatory failure in a horse is described. The response to intravenous fluid therapy was monitored by measurement of heart and respiratory rates, and arterial and central venous pressures. Heart rate was an unreliable guide to improved circulatory status. Central venous pressure and indirect arterial blood pressure were valuable guides to the efficacy of fluid therapy. 相似文献
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Evaluation of the agar gel immunodiffusion test for diagnosis of subclinical paratuberculosis in cattle 总被引:2,自引:0,他引:2
Concurrent bacteriologic culture of feces and agar gel immunodiffusion (AGID) testing was performed on all cows and bred heifers over 14 months old in 10 dairy herds during a 32-month period to determine the effectiveness of the AGID test for the detection of subclinical paratuberculosis. Herds were sampled 5 times and, when possible, culled animals were tested again at slaughter. During 5 herd-wide samplings, Mycobacterium paratuberculosis was isolated from 139 fecal specimens obtained from 109 cattle. Results of the AGID test were simultaneously positive 40 of 139 times (28.8%). Thirty-six of the 109 cattle (33.0%) determined to be infected had a positive AGID test result at some point during the 5 herd-wide samplings. When results of tests performed at time of slaughter were included, 117 cattle were identified as infected by culture methods; 55 of these (47.0%) were AGID test-positive at some point during the study. The upper limit of the maximal false-positive rate for the AGID test was 2.1%. On the basis of colony counts from cultures, subclinically infected cows shedding higher numbers of M paratuberculosis in their feces were more likely to have positive AGID test results (P less than 0.0001). In known infected cattle, neither the culture nor AGID test results were consistently positive on repeated testing. Of 48 official calfhood paratuberculosis vaccinates tested as adults, 3 had positive AGID test results and in 1 of these, M paratuberculosis was also isolated from the feces, indicating that the rate of false-positive AGID test results in calfhood vaccinates is low. 相似文献
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The leaf water conductance of cut, flowering stems of Chrysanthemum morifolium was measured by diffusion porometry. The stems were placed in solutions of chemicals which have commonly been used in flower preservatives, or which might be expected to affect the physiology of the leaves.In the environmental conditions of our experiments (18° C; 0.8 kPa; 5 W m?2 visible radiation for 8 h) sucrose (6 %) and abscisic acid (0.001 %) lowered leaf water conductance. Silver nitrate (0.003 %) or 8-hydroxyquinoline sulphate (0.02 %) either had no effect or increased leaf water conductance. We conclude that the latter two substances increase the vase life of cut flowers by affecting the physiology and pathology of the stem rather than the stomatal physiology of the leaf. The leaves of stems standing in high concentrations of sucrose accumulated sucrose and were frequently damaged as a result.The results are discussed with regard to the water relations of the cut flower and the possible use of anti-transpirants. 相似文献
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In adult cyclic female rats, intravenous injections of an antiserum to testosterone prevented the continued increase in serum follicle-stimulating hormone (FSH) which normally occurs during the early morning hours of estrus. This treatment did not prevent the initial increases in serum FSH (and luteinizing hormone) which occur during the critical period (1400 to 2000 of proestrus), nor did it interfere with subsequent ovulation. These observations indicate the existence of two separate mechanisms for preovulatory FSH release in the rat and implicate circulating testosterone as the stimulus for continued secretion of FSH during estrus. 相似文献
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The California net energy system has gained wide acceptance as a method for predicting rates of gain in growing and finishing beef animals. Researchers at the University of Kentucky, in co-operation with agricultural scientists in two regional research projects, NC-114 and S-156, have developed an interactive model that enhances the usefulness of the net energy system by including skeletal size, feed quality, temperature and relative humidity to determine feed intake and utilisation. Basically, the intake based on feed availability, nutrient composition, potential skeletal size and heat loss potential. After the feed is consumed, it is utilised according to the productive status of the animal, i.e. growth, lactation, foetal development, etc., using a modified form of the net energy system to predict weight change.The model allows a researcher to easily modify environment, feed, breed characteristics and productive status so as to evaluate their influence on the performance of the animal. 相似文献
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