金丝桃素、绿原酸和硬葡聚糖对草鱼非特异性免疫功能的影响

在水温（25±2）℃下，给饲养在网箱（1.0m×0.5m×1.0m）中体质量（110±5）g的草鱼（Ctenopharyngodon idellus）投喂添加了金丝桃素（0、0.066%、0.132%）、绿原酸（0、0.04%、0.08%）和硬葡聚糖（0、0.2%、0.4%）饲料，以基础饲料组为对照组，探讨三种添加剂对草鱼幼鱼血清溶菌酶活性、白细胞吞噬率和血清补体C3含量的影响。结果表明：0.2%硬葡聚糖组草鱼溶菌酶活性最高，显著高于对照组（P＜0.05），饲喂35d后溶菌酶活性达到峰值，而金丝桃素和绿原酸对草鱼幼鱼血清溶菌酶活性没有显著性影响；饲料中添加0.08%绿原酸组草鱼血液中白细胞吞噬率和血清补体C3含量均显著高于对照组（P＜0.05），但与添加0.2%和0.4%硬葡聚糖组没有显著性差异（P＞0.05）；添加0.132%金丝桃素组的血清中补体C3含量在最低，且显著低于对照组（P＜0.05）。饲料中添加0.08%绿原酸和0.2%硬葡聚糖可有效增强草鱼幼鱼非特异免疫功能。

Effects of Hypericin,Chlorogenic acid and Scleroglucan as Diet Supplements on the Non- specific Immune Response in Grass Carp Ctenopharyngodon idellus

Grass carp （Ctenopharyngodon idellus ） juveniles were fed on basal diets supplemented with different levels hypericin （0, 0.066% and 0.132% ）, chlorogenic acid （0,0.04% and 0.08%） and scleroglucan （0,0.2% and 0.4%） for 42 days to evaluate the effects of the additives on lysozyme activity, phagocytic rate and complement C3 concentration in grass carp. There was significantly higher lysozyme activity in 0.2% scleroglucan group than that in the control group （P〈0.05）, the maximal lysozyme activity in the 0.2% scleroglucan group on the 35th day. However, there were no significant increase in the lysozyme activities in both hypericin groups and chlorogenic acid groups （P〉0.05）. The phagocytic rate and complement C3 concentration were shown to be significantly higher in 0.04% chlorogenic acid group than those in the control group （P〈0.05）. There were no significant differences in the phagocytic rate and complement C3 concentration in 0.2% and 0.4% scleroglucan groups compared to 0.08% chlorogenic acid group. The minimal complement C3 concentration was found in the fish fed the diet containing 0.132% hypericin, significantly lower than that in the control group （P〈 0.05 ）. The findings indicate that the diets supplemented with 0.08% of chlorogenic acid or 0.2% of scleroglucan improve the nonspecific immune responses in grass carp juveniles.