摘要： 本研究旨在观察不同水平瘤胃保护性亮氨酸及β-羟基-β-甲基丁酸钙（HMB-Ca）对绒山羊免疫机能的影响。选用21只健康的内蒙古白绒山羊半同胞羯羊，按体重随机分为7组，对照组饲喂基础饲粮，6个试验组在基础饲粮基础上分别添加HMB-Ca 0.5 g/d（A组）、HMB-Ca 1.0 g/d（B组）、HMB-Ca 1.5 g/d（C组）、亮氨酸0.5 g/d（D组）、亮氨酸1.0 g/d（E组）、亮氨酸1.5 g/d（F组）。结果表明，添加不同水平保护性亮氨酸、HMB-Ca均可提高机体血清溶菌酶的含量（P＜0.05），提高血清中免疫球蛋白G的含量、免疫球蛋白M的含量，降低血清中可溶性CD4和CD8的含量，其中C组的效果最好（P＜0.05）。结果提示，饲料中添加保护性亮氨酸、HMB-Ca可增强机体的免疫机能。

The study was to observe the effects of different levels of rumen-protected leucine (Leu) and β-hydroxy β-methylbutyrate-Ca (HMB-Ca) on immune function of Inner Mongolian White Cashmere goats （IMWCG）. Twenty-one wethers of IMWCG in half-sib were randomly divided into 7 groups according to body weight. Goats in control group were fed basal diet, goats in the six experimental groups were fed diets supplemented with different levels of Leu and HMB-Ca ［0.5 g/d HMB group (group A), 1.0 g/d HMB group (group B), 1.5 g/d HMB group (group C), 0.5 g/d Leu group (group D), 1.0 g/d Leu group (group E) and 1.5 g/d Leu group (group F)］. The results suggested that different levels of rumen-protected Leu and HMB-Ca could increase lysozyme （P＜0.05）, IgG and IgM contents in serum, but decrease the levels of serum soluble CD4 and CD8, and group C got the best effects (P＜0.05). The experiment indicates that rumen-protected Leu and HMB-Ca play important roles in enhancing the body immune function.［Chinese Journal of Animal Nutrition, 2010，22（6）:1762-1767］