虾青素对马苏大麻哈鱼生长性能、抗氧化能力及非特异性免疫的影响OA

In order to study the effects of astaxanthin(AST)on the growth performance,digestive enzyme activity,antioxidant capacity and non-specific immunity of Oncorhynchus masou,450 healthy individuals[initial body weight(1.15±0.03)g]were randomly divided into 5 groups with 3 replicates per group and 30 fish per replicate.The fish were fed a basal diet(control group)and four experimental diets(groups A1,A2,A3 and A4)supplemented with 30,60,90 mg/kg and 120 mg/kg AST in basic diet for 56 d.The results showed that the final body weight,average weight gain rate,specific growth rate and feed effi-ciency of Oncorhynchus masou in groups A1,A2,A3 and A4 were significantly higher than those in the control group(P<0.05);additionally,these indices in groups A2,A3 and A4 were signifi-cantly higher than those in the control group and group A1(P<0.05).Compared with the control group,the activities of trypsin,α-amylase and lipase in the liver and intestine of fish in groups A2,A3 and A4 were significantly increased(P<0.05),the activities and contents of antioxidant enzymes in serum and liver were increased in varying degrees,and the malondialdehyde(MDA)content was significantly reduced(P<0.05).Compared with the control group,the non-specific immune indices of Oncorhynchus masou groups A2 and A3 were significantly increased(P<0.05),with the most significant improvement observed in group A2.Under the conditions of this experiment,dietary AST supplementation in groups A2 and A3 could effectively improve the growth performance,digestive enzyme activity,antioxidant capacity and non-specific immunity of Oncorhynchus masou.To achieve the maximum average weight gain rate of Oncorhynchus masou,the rec-ommended dietary AST supplementation level was 72.68 mg/kg.