Effects of Dietary Enzymatic Fish Peptides on Growth,Metamorphosis,Liver Metabolism and Antioxidant Capacity of Bullfrog Tadpoles(Lithobates catesbeiana)Fed Low Fish Meal Diets
The aim of this study was to investigate the effects of a low fish meal diet supplemented with enzy-matic fish peptides on growth,metamorphosis,liver metabolism and antioxidant capacity of bullfrog tadpole.A total of 4 800 tadpoles with an initial body weight of 0.04 g were randomly divided into 5 groups with 3 repli-cates per group and 320 tadpoles per replicate,and fed 5 different isoniazid and isolipid diets,respectively.A 15％fish meal diet(FM15 group)was set as the control,and two diets with different fish meal levels were set as 10％and 5％,respectively.In each diet,2.5％and 5.0％enzymatic fish peptides were added,which were recorded as F10E2.5,F10E5,F5E2.5 and F5E5 groups,respectively.The experimental feeding lasted for 65 days.The results showed as follows:1)compared with FM15 group,the addition of enzymatic fish peptides could increase the metamorphosis and survival rate of tadpoles,among which the metamorphosis of bullfrog tadpoles in the F10E5 group was significantly increased(P＜0.05).2)Compared with the FM15 group,the addition of enzymatic fish peptides except for F5E2.5 group increased intestinal lipase activity of bullfrog(P＜0.05).3)Compared with FM15 group,the addition of enzymatic fish small peptides could significantly in-crease the intestinal superoxide dismutase(SOD)activity of bullfrogs(P＜0.05),in addition,the intestinal glutathione peroxidase(GSH-Px),catalase(CAT)activities and glutathione(GSH)content in F10E5 group were significantly increased(P＜0.05).4)Compared with FM15 group,the addition of enzymatic fish pep-tides significantly increased the relative expression level of sulfotransferase(SULT)gene in the intestine of bullfrogs(P＜0.05),and the F10E5 group significantly increased the relative expression level of CAT,SOD,and glutathione S-transferase(GST)genes(P＜0.05).5)Except for the F5E5 group,the addition of enzy-matic fish peptides improved the vacuolisation of bullfrog hepatocytes.6)Compared with FM15 group,the ad-dition of enzymatic fish peptides significantly increased the hepatic aspartate aminotransferase and acid phospha-tase activities of bullfrogs(P＜0.05),and the hepatic alanine aminotransferase activity of bullfrogs were signif-icantly increased after adding 5.0％enzymatic fish peptides(P＜0.05).In conclusion,dietary supplementation of 10％fish meal and 5.0％enzymatic fish peptides(F10E5)can improve metamorphosis rate,survival rate and antioxidant capacity of bullfrog tadpoles without affecting growth.[Chinese Journal of Animal Nutrition,2024,36(1):478-489]
enzymatic fish peptidesbullfrog tadpolesgrowthmetamorphosisantioxidant
万方数据
维普
