青稞秸秆对生长期藏绵羊体增重及免疫指标的影响

本试验用青稞秸秆替代燕麦干草作为唯一粗饲料来源,研究其对生长期藏绵羊体增重及免疫功能的影响。选择18只4~5月龄健康河谷型藏绵羊,随机分为2组,即:青稞组(青稞秸秆300 g/d+精料300 g/d)和燕麦组(燕麦干草300 g/d+精料300 g/d)。试验期4周,第1周为预试期,第2~4周为正试期。正试期结束后,按公母各占1/2原则,各组分别选取6只羊屠宰采样。结果发现:青稞组与燕麦组藏绵羊的体重、日增重、脾脏重和脾脏指数均差异不显著(P0.05);青稞组与燕麦组藏绵羊血清中免疫球蛋白(Ig)G、Ig A、Ig M、溶菌酶含量和酸性磷酸酶活性均差异不显著(P0.05),但青稞组中溶菌酶含量有高于燕麦组的趋势(P=0.083);青稞组与燕麦组血清、胸腺和脾脏白细胞介素(IL)-2、IL-4、IL-6、IL-10和干扰素γ(IFN-γ)含量均差异不显著(P0.05)。综合来看,与燕麦干草相比,饲喂青稞秸秆不会降低生长期藏绵羊的体增重及免疫性能,且有提高机体非特异性免疫因子(溶菌酶)含量的潜力,可作为藏绵羊的粗饲料来源。

Effects of Highland Barley Straw on Body Weight Gain and Immune Indexes in Growing Tibetan Sheep

Highland barley straw was used to substitute oat hay for the study on the effects on body weight gain and immune indexes in growing Tibetan sheep. Eighteen healthy 4-to 5-month old Valley Tibetan sheep were selected and randomly divided into 2 groups, which were highland barley group ( highland barley straw 300 g/d+concentrate 300 g/d) and oat group ( oat hay 300 g/d +concentrate 300 g/d) . Test period lasted for 4 weeks, the 1st week was pre-test period, the 2nd to 4th weeks were formal test period. After formal test peri-od, according to the principle of half-and-half of ewe and ram, six sheep per group were selected to slaughter and sample. The results showed as follows:body weight, daily gain, spleen weight and spleen index in Tibet-an sheep between highland barley group and oat group were not significantly different ( P>0.05); serum im-munoglobulin ( Ig) G, IgA, IgM and lysozyme contents acid, and phosphatase activity showed no significant difference between two groups ( P>0.05) , but lysozyme content in highland barley group had a trend to be im-proved compared with that in oat group ( P=0.083); interleukin ( IL)-2, IL-4, IL-6, IL-10 and interferon γ( IFN-γ) contents in serum, thymus and spleen in two groups were not significantly different ( P>0.05) . As a whole, compared to oat hay, feeding highland barley straw to Tibetan sheep can’ t reduce body weight gain and impair immune function, and it has the potential to improve the content of lysozyme as a non-specific im-mune factor in serum. Highland barley straw can be used as a source of roughage for Tibetan sheep.