饲料中胰酶添加水平对大口黑鲈幼鱼生长性能、生化指标和肝肠组织结构的影响OA北大核心CSTPCD

To evaluate the effects of dietary pancreatin on growth performance,biochemical indexes,and enterohepatic structure of juvenile largemouth bass(Micropterus salmoides),specimens with of the initial body quality of(8.00±0.50)g,630 were randomly divided into 6 groups,each group of three repetition,35 fishes each repetition.The control group was fed with a basic diet,and 5 experimental groups were fed with pancreatin-added diet of different concentrations of pancreatin(P250,P500,P750,P1000,P1250).The experimental period was 70 days.The results show that:The growth performance of fish first increased and then decreased with the increase of pancreatin dosage.The final average weight,weight gain rate and specific growth rate of fish in P750 group were the highest,and the feed ratio was the lowest,which were significantly different from the control group.Compared with the control group,the contents of serum total protein and albumin increased,which were the highest in P500 group and P750 group,respectively.The contents of serum triglyceride and total cholesterol in the P500 and P750 groups decreased significantly.The activities of aspartate aminotransferase(AST)and alanine aminotransferase(ALT)first decreased and then increased with the increasing amount of trypsin added.In the P750 group,the activity of AST was the lowest,and the activity of alkaline phosphatase was the highest.Compared with the control group,the P500 and P750 groups had a significant reduction in lipid vacuolization area and a significant increase in villus width;Fluff number increased significantly in the P500 group.In conclusion,dietary pancreatin could significantly improve the growth performance,biochemical indexes,liver antioxidant and enterohepatic structure of largemouth bass,and there was a dose effect of pancreatin.Based on the comprehensive analysis and the index of weight gain rate,it is suggested that the appropriate amount of pancreatin in the diet of largemouth bass is 679 mg/kg.