日粮能量水平对1.5～3.5月龄獭兔免疫性能及肝脏IFN-γ表达的影响

Effect of diet energy level on immune function and expression of hepatic IFN-γgene of 1.5-3.5 months old rex rabbits

【目的】研究日粮不同能量水平对獭兔免疫性能及IFN-γ表达量的影响,为獭兔饲养能量标准的制定提供科学依据。【方法】将160只1.5月龄獭兔随机分为Ⅰ、Ⅱ、Ⅲ、Ⅳ4组,每组40只,分别饲喂消化能为9.7,10.5,11.3和12.1MJ/kg的4种日粮（各日粮其他营养成分一致）;预试期7d,正试期2个月;每个月采样1次,进行相关免疫指标的测定。【结果】在日粮能量水平为9.7~11.3 MJ/kg时,獭兔的免疫器官指数、免疫球蛋白含量以及肝脏IFN-γ表达量均随日粮能量水平的升高呈现出一定的规律性。2.5月龄时,Ⅰ组与Ⅳ组肝脏指数、脾脏指数、IgG含量以及肝脏IFN-γ表达量的差异均达到了显著水平（P〈0.05）。3.5月龄时,Ⅰ组与Ⅲ组的脾脏指数、IgG和SIgA含量及Ⅰ组与Ⅳ组的肝脏IFN-γ表达量均差异显著（P〈0.05）。【结论】在日粮能量水平为9.7~11.3MJ/kg时,日粮能量水平的升高能够增大獭兔的免疫器官指数,促进獭兔免疫球蛋白的分泌以及肝脏IFN-γ的表达,獭兔日粮较适宜的消化能水平为11.3MJ/kg。

[Objective] The experiment was conducted to investigate the effect of diet energy level on immune function and hepatic IFN-γ expression of rex rabbits. [Method] 160 weaned rex rabbits with age of 1.5 months were randomly divided into Ⅰ , Ⅱ ,Ⅲ and Ⅳ 4 groups with 4 replicates per group and 10 rabbits per replicate. DE values of diets fed to rabbits were 9.7（Group Ⅰ）,10.5（Group Ⅱ ）,11. 3（Group Ⅲ）,and 12. 1（Group Ⅳ） MJ/kg,respectively. Other nutritional ingredients were kept consistent. The experiment included a pretrial period of 7 days and an experimental period of 2 months. Samples were collected every month to measure immune indices. [Result] Immune organ index, immune globulin content and expression of hepatic IFN-7 changed as the energy levels increased from 9.7 to 11.3 MJ/kg. Group Ⅰ and Group Ⅳ had significant difference in hepatic index,IgG content,SIgA content and expression of hepatic IFN-γ, when the age was 2. 5 months （P〈0. 05）. Group Ⅰ and Group Ⅲ had significant difference in spleen index,IgG content, SIgA content and expression of hepatic IFN-γ when the age was 3. 5 months （P〈0.05）. [Conclusion] Increasing diet energy level in a certain range could enhance the immunity of rex rabbits. The suggested diet digestible energy level was 11.3 MJ/kg.