Effects of Dietary Protein and Lipid Levels on Growth, Body Composition and Digestive Enzyme Activity in Juvenile Grass Carp Ctenopharyngodon idellus
Six hundred and seventy five grass carp (Ctenopharyngodon idellus) juveniles (body weight 35.59 t 0.44g) were randomly divided into nine groups with triplication,stocked into net cages displaced in an indoor tank and fed one of the nine diets containing three protein levels (24％,28％ and 32％,fishmeal and soybean meal as dietary protein) and three lipid levels (4％,6％ and 8％,soybean oil as dietary lipid) for 92 days to evaluate the effects of dietary protein and lipid levels on the growth performance and digestive enzyme activities of grass carp.The results showed that specific growth rate was found significantly higher in the fish fed the diet D4 (containing 28.02％ protein,and 4.30％ fat) than that in the fish fed the other diets (P＜ 0.05).There was significantly higher proteinase activity in the fish fed the diet D4 than those in the fish fed diets D1,D8 and D9 (P＜ 0.05).It is recommended that the optimal ratio of protein level to energy (P/E) be 28.02/19.58,optimal dietary proten level 28.02％ and optimal energy 14307 kJ· kg-1,for grass carp juveniles.
NETL
NSTL
万方数据
维普
