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排序方式: 共有350条查询结果,搜索用时 15 毫秒
41.
Encephalitis in horses in Hillsborough County, Florida, 1964 总被引:1,自引:0,他引:1
W L Jennings R A Kathein A L Lewis J O Bond 《American journal of veterinary research》1967,28(125):965-970
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The pathology of Trypanosoma brucei infection in the rat 总被引:6,自引:0,他引:6
M Murray P K Murray F W Jennings E W Fisher G M Urquhart 《Research in veterinary science》1974,16(1):77-84
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Patient monitoring devices may be considered as extensions of the veterinary clinician's senses. Many of the parameters outlined above have been used for years, without the term “monitor” being used. In this report, several patient monitoring methods have been discussed, and their advantages weighed. It is hoped that judicious use of some of these monitoring methods may aid the veterinary clinician in diagnosis and treatment of his trauma patients. 相似文献
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Ogden RK Coblentz WK Coffey KP Turner JE Scarbrough DA Jennings JA Richardson MD 《Journal of animal science》2005,83(5):1142-1152
Southern crabgrass (Digitaria ciliaris [Retz.] Koel.) is often viewed as an undesirable weed, largely because it encroaches upon field and forage crops, gardens, and lawns. However, visual observations of livestock grazing mixed-species pastures suggest that cattle seem to prefer crabgrass to many other summer forages. The objectives of this study were to assess the nutritive value of crabgrass sampled weekly between July 11, and August 22, 2001, and then to determine ruminal in situ disappearance kinetics of DM and NDF for these crabgrass forages. A secondary objective was to compare these kinetic estimates with those of alfalfa (Medicago sativa L.), bermudagrass (Cynodon dactylon [L.] Pers.), and orchardgrass (Dactylis glomerata L.) control hays. All forages were evaluated in situ using five (383 +/- 22.7 kg) ruminally cannulated crossbred (Gelbvieh x Angus x Brangus) steers. Whole-plant crabgrass exhibited more rapid (P < or = 0.002) ruminal disappearance rates of DM (overall range = 0.069 to 0.084 h(-1)) than did bermudagrass (0.054 h(-1)) and orchardgrass (0.060 h(-1)) hays, but disappearance rates were slower (P < 0.001) for crabgrass than for alfalfa hay (0.143 h(-1)). Effective ruminal disappearance of DM was greater (P < 0.001) for crabgrass (overall range = 69.3 to 75.4%) than for all the control hays. Similarly, disappearance rates of NDF for crabgrass (overall range = 0.069 to 0.086 h(-1)) were more rapid (P < 0.001) than observed for bermudagrass and orchardgrass hays; however, NDF in alfalfa disappeared at a faster (P < 0.001) rate (0.107 h(-1)) than crabgrass. These results indicate that crabgrass offers greater effective ruminal degradability of DM and NDF than orchardgrass or alfalfa of moderate quality. More importantly, it potentially offers faster and more extensive ruminal disappearance than perennial warm-season grasses typically found throughout the southeastern United States, and it should likely support improved performance by ruminant livestock in this region. 相似文献
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Because of the type of patient treated, and the nature of the injury, the veterinarian is often called upon to treat surgical infections. These infections may be primary, or can be sequelae or trauma or elective surgery. Each clinician has his own protocol and priorities in evaluation of the patient with a surgical infection. A careful history and physical examination, together with clinical and microbiological laboratory testing procedures will help identify the pathogenic organism and indicate the severity of the infection in the animal patient. With this preliminary evaluation, the clinician and surgeon may attack the problem appropriately, and with a greater assurance of success. 相似文献
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A model for the description and prediction of the response of laying hens to amino acid intake 总被引:4,自引:0,他引:4
A model which describes the response of groups of laying hens to different levels of amino acid intake is presented. The model is based on the assumption of simple linear relationships between amino acid intake and the output characteristics, egg production and maintenance, for individual birds. The response for a group of birds is then derived as the average of the individual responses. The shape of this flock—response curve depends on seven parameters, namely the mean maximum egg output (ē max), variation in E max, mean body weight (W), variation in W, the correlation between egg output and body weight, and two constants (a and b) representing respectively the quantities of amino acid required for unit egg output and for maintenance of unit body weight.
Three methods of manipulating the model are described. These use (i) a computer simulation procedure; (ii) the exact solution for the model and (iii) some reasonable approximations for practical application.
The use of the model for describing experimental data and for predicting amino acid requirements is discussed, and the main limiting assumptions and some possible extensions of the principles involved are pointed out. 相似文献
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