Effects Of Different Levels Of Resveratrol And Stevioside On Growth Performance,Digestive Enzyme Activity,Antioxidant Capacity And Gene Expression Of Songpu Mirror Carp

Those experiments was conducted to study the effects of different levels of resveratrol and stevioside on the growth performance,intestinal digestive enzyme activities,live antioxidant indices,biochemical indices and gene expression of Songpu mirror carp.The results can be applied to aquaculture.The diets of each group were supplemented with 0,80,160,240,320 and 400mg/kg resveratrol and stevioside,respectively.The experiment fish purchased from the Hulan Station of the Heilongjiang Fisheries Research Institute.720 juvenile Songpu mirror carp with initial weight of(3.00±0.15)g were randomly allocated into 6 groups with 4 replicates per group and 30 fish per replicate and 540 juvenile Songpu Mirror carp were randomly allocated into 6 groups with 3 replicates per group and 30 fish per replicate.The experiment lasted for 56 days.The results are as follows:(1)Different levels of resveratrol had no significant effect on weight gain,condition factor(CF)and hepatopancreas somatic indices(HSI)(P>0.05).Feed coefficient(FCR)and visceral somatic indices(VSI)of 240 and 320mg/kg resveratrol were significantly decreased(P<0.05).The dietary stevioside increased the weight gain and decreased HSI(P<0.05);the FCR of 160 and 240mg/kg stevioside decreased significantly(P<0.05);different levels of stevioside had no significant effect on VSI and CF(P>0.05).Different levels of resveratrol and stevioside had no significant effect on moisture,crude protein,crude lipid and crude ash content of Songpu mirror carp(P>0.05).(2)Compared with the control group,the activity of superoxide dismutase(SOD),catalase(CAT)in liver increased significantly(P<0.05)and content of malondialdehyde(MDA)decreased significantly(P<0.05)by supplementation of160mg/kg resveratrol.The liver SOD activity,CAT activity increased significantly(P<0.05)and the MDA content decreased significantly(P<0.05)by adding 240mg/kg stevioside.The alkaline phosphatase(AKP),acid phosphatase(ACP),total serum protein(TP)and albumin(ALB)increased significantly(P<0.05)by supplementation160mg/kg resveratrol.The total serum protein(TP)and total cholesterol(CHOL)were significantly increased(P<0.05)with 240mg/kg stevioside,there was no significant effect on other serum indicators(P>0.05)with different levels of stevioside.Serum glutamic oxaloacetic transaminase(AST)and alanine transaminase(ALT)with different levels of resveratrol and stevioside had no significant difference(P>0.05).(3)Compared with the control group,the activities of amylase and protease in the midgut increased significantly(P<0.05),the activities of lipase in the foregut and midgut increased significantly(P<0.05),the activities of amylase in the midgut decreased significantly(P<0.05)in 240 and 400mg/kg resveratrol,the activities of protease in the foregut increased significantly in 80 and 320mg/kg resveratrol groups.The activities of amylase,lipase and protease in foregut and midgut were significantly increased by adding 160mg/kg(P<0.05)and 240mg/kg stevioside(P<0.05).(4)Relative gene expression of TNF-? and MyD88 increased significantly(P<0.05)when 400mg/kg resveratrol was added,but the expression of IL-1? gene was not affected by resveratrol(P<0.05).The gene expression of TNF-? increased significantly when 240mg/kg stevioside was added(P<0.05),the expression of IL-1? increased significantly when320mg/kg stevioside was added(P<0.05),and the expression of MyD88 increased significantly when 160mg/kg steviosid was added(P<0.05).In conclusion,dietary supplementation of resveratrol and stevioside can improve the liver antioxidant activity,intestinal digestive enzyme activity and immune function of fish,the recommended addition level are 160mg/kg resveratrol and 240mg/kg stevioside.