本文探讨了饲粮不同苏氨酸水平对断奶至2月龄生长肉兔生长性能、氮代谢、免疫功能和血清生化指标的影响。选用断奶生长肉兔200只，随机分成5组，每组40个重复，每个重复1只兔，分别饲喂在基础饲粮中苏氨酸添加水平为0、0.1%、0.2%、0.3%、0.4%的试验饲粮，预试期7 d，正试期23 d。结果表明：在初始重无显著差异的情况下，饲粮添加苏氨酸能极显著提高平均日采食量（ADFI）（P<0.01），对平均日增重（ADG）和料重比（F/G）影响显著（P<0.05）。饲粮苏氨酸水平对食入氮（IN）有显著影响（P<0.05），对可消化氮（DN）、沉积氮（RN）、氮表观消化率（DN/IN）无显著影响（P>0.05）。血清免疫球蛋白A（IgA）、免疫球蛋白M（IgM）和免疫球蛋白G（IgG）含量随饲粮苏氨酸水平的增加均无显著变化（P>0.05）。饲粮苏氨酸水平对血清碱性磷酸酶活性有显著影响（P<0.05），对总蛋白（TP）、甘油三酯（TG）含量影响不显著（P>0.05）。综合本试验测定指标，断奶至2月龄生长肉兔饲粮中的苏氨酸适宜水平为069%。

The experiment was conducted to study the effects of dietary threonine levels on growth performance, serum immune and biochemical indices of weaning to 2-month-old meat rabbits. Two hundred weaning meat rabbits were randomly assigned to 5 groups with 40 replicates in each group and 1 rabbit in each replicate. Rabbits in the 5 groups were fed basal diet supplemented with 0, 0.1%, 0.2%, 0.3% and 0.4% threonine, respectively. The trial lasted for 7 days for adaptation, and 23 days for test. The results showed that dietary threonine supplementation significantly increased average daily feed intake (ADFI) (P<0.01), and significantly affected average daily gain (ADG) and feed/gain (F/G) of the rabbits (P<0.05) when the initial body weight was not significantly different. The dietary threonine levels had a significant influence on nitrogen intake (IN) (P<0.05), but had no significant influences on digestible nitrogen (DN), retained nitrogen（RN）and DN/IN （P>0.05）. With the increase of threonine levels, the serum concentrations of immunoglobulin A, immunoglobulin M and immunoglobulin G had no significant changes (P>0.05). The dietary threonine levels had a significant influence on the activity of serum alkaline phosphatase (AKP) (P<0.05), but had no significant influences on the contents of total protein (TP) and triglyeride (TG) (P>0.05). In conclusion, the appropriate dietary level of threonine for the weaning to 2-month-old meat rabbits is 0.69%.［Chinese Journal of Animal Nutrition，2011，23（4）：703 -708］