山豆根多糖对罗非鱼生长性能和免疫功能的影响

本试验旨在探究饲粮中添加不同剂量山豆根多糖对罗非鱼生长性能和免疫功能的作用。试验选取400尾体格健壮的吉富罗非鱼随机分为5组，每组4个重复，每个重复20尾罗非鱼，各组在基础饲粮中分别添加0（CK组）、1.0（SSP 1组）、2.0（SSP 2组）、4.0 g/kg （SSP 3组）山豆根多糖和20 mg/（kg·BW·d）黄芪多糖（APS组），试验期30 d。试验结束时测定吉富罗非鱼增重率（WGR）、特定生长率（SGR）、饲料系数（FCR）等生长指标和罗非鱼血液生理生化指标及血清和肝脏中非特异性免疫指标。结果表明，与CK组相比，SSP 1和SSP 2组吉富罗非鱼WGR、SGR水平及FCR系数无显著变化（P>0.05），SSP 1组血清中胆固醇（TC）和总蛋白（TP）水平显著降低（P<0.05），各试验组（SSP 1、SSP 2、SSP 3和APS组）罗非鱼肝脏和脾脏的脏器指数无显著差异（P>0.05），IL-12水平显著升高（P<0.05），SSP 2和SSP 3组IL-2水平显著升高（P<0.05），IFN-γ水平显著降低（P<0.05）；SSP 1和SSP 2组罗非鱼过氧化物酶（POD）和谷胱甘肽过氧化物酶（GSH-Px）活性极显著升高（P<0.01）。综上所述，在饲料中添加适量山豆根多糖对罗非鱼的生长、抗氧化能力和免疫功能有一定的促进作用，以添加量2.0 g/kg为最佳。

Effects of Sophora subprosrate Polysaccharide on Growth Performance and Immune Function of Oreochromis niloticus

This experiment was designed to investigate the effects of different doses of Sophora subprosrate polysaccharide (SSP) on the growth and immune function of Oreochromis niloticus. In the test, 400 tails of Oreochromis niloticus were randomly divided into 5 groups with 4 replicates per group and 20 Oreochromis niloticus per replicate. The animals were fed the basal diet supplemented with 0 (CK group), 1.0 (SSP 1 group), 2.0 (SSP 2 group), 4.0 g/kg (SSP 3 group) SSP and 20 mg/(kg·BW·d)(APS group), respectively. The experiment period was 30 d. At the end of the experiment, Astragalus polysaccharide the growth indices, such as weight gain rate (WGR), specific growth rate (SGR)and feed conversion ratio (FCR), blood physiological and biochemical indexes, serum and liver nonspecific immunity indexes of Oreochromis niloticus were determined. The results showed that compared with CK group, there were no significant changes in WGR, SGR and FCR in SSP 1 and SSP 2 groups (P>0.05). The levels of cholesterol (TC) and total protein (TP) in serum were significantly decreased (P<0.05), the organ indices of liver and spleen of Oreochromis niloticus in experimental groups (SSP 1, SSP 2, SSP 3 and APS groups) were no significent changes (P>0.05), IL-12 level was significantly increased (P<0.05). The levels of IL-2 were increased (P<0.05) and the levels of IFN-γ were decreased (P<0.05) in SSP 2 and SSP 3 groups. The activities of POD and GSH-Px of Oreochromis niloticus in SSP 1 and SSP 2 group were significantly higher than those in the CK group (P<0.01). In brief, SSP could promote the growth, antioxidant capacity and immune function of Oreochromis niloticus, and the optimal supplemental level of SSP was 2.0 g/kg.