Study On Vitamin C，Vitamin E, Choline Requirement Of Juvenile Giant Croaker Nibea Japonica

This paper contains three experiments. This experiment was conducted to study the effects of dietary vitamin C, vitamin E and choline on growth, body composition and tissue vitamin concentrations in juvenile giant croaker (Nibeajaponica), and thus to evaluate the optimal vitamin C, vitamin E and choline requirement of juvenile Nibeajaponica. Each group of diet was fed respectively to3replicates and each replicate contained15fish with initial weight about8.15g. The experiment was done in PE fish tank and lasted for eight weeks. The main research results are as follows:1.Study on Vitamin C Requirement of Juvenile Giant Croaker NibeajaponicaSix iso-nitrogenous and iso-energetic diets with levels of0,50,150,300,600,1200mg/kg L-ascobyl-2-monophosphate were formulated to evaluate the optimal Vc requirement of juvenile Nibeajaponica.Resuhs indicated that, WG and SGR offish groups fed no Vc addition diet were significantly lower than groups with diet Vc content from50to150mg/kg. PER of fish groups fed no Vc addition diet were significantly lower than groups with diet Vc content from150to1200mg/kg.The content of Vc in liver and muscle were increased with the increasing levels of feed Vc content, and particularly evident in the0～150mg/kg. Index of growth performance and tissue Vc accumulation of the juvenile Giant Croaker, the optimal vitamin C requirement in the form of L-ascobyl-2-monophosphate is about150mg/kg.2.Study on Vitamin E Requirement of Juvenile Giant Croaker NibeajaponicaSix iso-nitrogenous and iso-energetic diets with levels of0,50,100,200,400,800mg/kg dl-a-Tocopheryl acetate were formulated to evaluate the optimal vitamin E requirement of juvenile Nibea japonica. Results indicated that, WG and SGR of fish groups fed no vitamin E addition diet were significantly lower than rest groups. The content of vitamin E in liver and muscle were increased with the increasing levels of feed vitamin E content, and particularly evident in the0～200mg/kg. The minimum vitamin E requirement to keep growth performance for juvenile Nibea japonica in the form of dl-a-Tocopheryl acetate is about50mg/kg. Index of tissue vitamin E accumulation, the maximum dietary available vitamin E level is about200mg/kg.3.Study on choline Requirement of Juvenile Giant Croaker NibeajaponicaSix iso-nitrogenous and iso-energetic diets with levels of0,250,500,1000,3000,5000mg/kg choline chloride were formulated to evaluate the optimal choline requirement of juvenile Nibea japonica. Results indicated that, WG, SGR and PER of fish groups fed no choline addition diet were significantly lower than groups with1000mg/kg diet choline FCR of fish groups fed no choline addition diet were significantly higher than groups with diet choline content from500to1000mg/kg.The content of choline in liver was increased with the increasing levels of feed choline content, and particularly evident in the0～1000mg/kg. It is also found that the fat content in liver decreased with the increase of feed choline supplementation level. Index of growth performance and tissue choline accumulation of the juvenile Giant Croaker, the optimal choline requirement in the form of choline chloride is about1000mg/kg.