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This discussion of legal issues that may arise from the existence of zoonotic diseases is not meant to cause alarm; rather, it is meant to alert members of the profession to possibilities, not probabilities. The very nature of any discussion of legal issues, especially a discussion of case law in which someone is always suing somebody else, exaggerates the true-life situation. Although it is everyone's hope that they will not be involved in litigation, it is wise to be aware of the problems that may arise in connection with zoonotic diseases. 相似文献
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E E Beaver J E Williams S J Miller D L Hancock S M Hannah D L O'Connor 《Journal of animal science》1989,67(9):2415-2425
Two split-plot designed experiments were conducted to determine the effects of breed (Angus, A, or Brangus, B) and diet (fescue hay, FH; corn silage, CS; or concentrate) on composition and rate of growth, diet digestibility and plasma hormones of steers. In Exp. 1, 10 steers (five of each breed) were fed a CS-based diet followed by a FH-based diet for two consecutive 60-d periods. Both breeds had lower (P less than .01) DM intake and digestibility when fed FH than when fed CS diets. The B steers had higher (P less than .01) plasma insulin concentrations than A steers when fed the CS diet. In Exp. 2, during two consecutive years, 10 steers previously fed CS- and FH-based diets were finished with a corn silage-whole shelled corn-based diet. During yr 1, A steers had higher (P less than .01) DM intake and plasma triiodothyronine (T3) and thyroxine (T4) concentrations (P less than .05) than B steers did. Although final weights were similar (P greater than .10), A steers had heavier (P less than .05) carcass weights than B steers did. During yr 2, A steers had higher (P less than .07) DM and starch digestibilities and higher (P less than .01) plasma T4 concentrations than B steers did. The greater (P less than .01) energetic efficiency of A steers was attributed to the greater rates of fat deposition during yr 2. Regardless of type of diet fed, A steers were more efficient at depositing energy. Higher circulating T4 concentrations of A than B steers may explain some of the physiological differences between these breeds. 相似文献