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141.
A control and a 10% fat-supplemented diet were fed to exercising horses maintained in two different body conditions, during both temperate and hot weather, to determine the efficacy of fat as dietary aid to reduced energy requirements for thermal regulation in exercising horses. Horses were worked 7.2 km daily, 5 d/w, and in each season were fed sufficient energy to maintain constant body weight and body fat content at each assigned level of body condition. In both seasons and in both body conditions, digestible energy intake was lower (P<.01) when the horses were fed the fat-supplemented diet than when fed the control diet. Digestible energy intake was partitioned into requirements for work and maintenance. Since work levels were similar, digestible energy requirements for work were similar when horses were fed both experimental diets. However, the digestible energy requirements for maintenance were significantly lower (P<.01) when the horses were fed the fat-supplemented diet. Thus, it appears that feeding fat to exercising horses reduces the thermal load and resulting digestible energy requirements for maintenance in both temperate and hot weather. 相似文献
142.
R. Evans 《Soil Use and Management》1990,6(3):125-131
Abstract. The 296 soil associations of the National Soil Map of England and Wales are placed into five categories of erosion risk. These are based on land use, landform and soil properties and take into account the extent of erosion in the uplands, and its frequency, extent and rates in the lowlands. Erosion of arable land is by water or wind, but in the uplands frost action and disturbance by sheep are also important. A large proportion of arable England (36%) is at moderate to very high risk of erosion, including much of the better drained and more easily worked land, especially sandy soils. In the uplands thin soils or deep peats are most at risk. If land use changes, because of increasing intensification of agriculture or in response to climatic changes, many soil associations will become more at risk of erosion. 相似文献
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The measurement of heart rate during exercise in the horse has been recommended as a means of prescribing work effort, monitoring the changes in aerobic capacity during training and as part of the clinical examination of the performance horse. The accuracy of four heart rate meters (PEH 100, PU 10, HR 14 and HRM-7) was assessed by comparison with heart rate determined by simultaneous telemetry electrocardiography (ECG) using a rapid incremental exercise test on a treadmill. Heart rate displayed by all four meters showed significant correlations with the ECG heart rate, but only two meters (PEH 100 and HRM-7) had correlation coefficients of 0.98 or greater. 相似文献
149.
R H Evans 《Veterinary Clinics of North America: Small Animal Practice》1987,17(3):755-783
This article considers the care and management of orphaned neonates and their rehabilitation and reintroduction into the wild. 相似文献
150.
Effects of various vaccination protocols on passive and active immunity to Pasteurella haemolytica and Haemophilus somnus in beef calves. 下载免费PDF全文
J Van Donkersgoed C Guenther B N Evans A A Potter R J Harland 《The Canadian veterinary journal. La revue veterinaire canadienne》1995,36(7):424-429
Two field trials were conducted in a beef cow herd in Saskatchewan to determine the effectiveness of a combined Pasteurella haemolytica and Haemophilus somnus vaccine in increasing passively and actively acquired antibodies in beef calves. Vaccination of dams at 4 and/or 7 weeks prepartum was associated with increased antibody titers to P. haemolytica and H. somnus in their serum (P < 0.05), colostrum (P < 0.05), and serum of their calves at 3 days and 1 month of age (P < 0.05). There was no significant (P > 0.05) difference in antibody titers in the colostrum and serum of calves from single or double vaccinated dams. Calves vaccinated at 1 and 2 months of age in the face of maternal antibodies to P. haemolytica and H. somnus had significantly (P < 0.05) higher antibodies to P. haemolytica and H. somnus at 4 and 6 months of age than did unvaccinated calves. Calves vaccinated at 3 and 4 months of age in the face of low levels of preexisting antibodies had significantly (P < 0.05) higher antibodies to P. haemolytica at 5 months of age and to H. somnus at 5 and 6 months of age than did unvaccinated calves. Calves vaccinated once at 4 months of age had significantly (P < 0.05) higher antibody titers to P. haemolytica and H. somnus at 4.5 months of age than did unvaccinated calves, but this difference was not apparent at 6 months of age.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献