This study has been conducted to examine the suitable amount of of the substitution of canola meal for soybean meal that can be used to grass carp Ctenopharyngodon idella L. diet , and investigate its effects on growth performance and the body composition . 96 fingerlings of grass carp (M.Wt = 11.33+ 1.43gm) are distributed randomly on three triplicates and four treatments .Using two diets were approximate in level of protein ( 24.49 + 0.38 %) and substitution ( 0 % ) as T1 and T3 respectively with two feeding in the day and substitution ( 5 % ) as T2 and T4 respectively with three feeding in the day . The experiment is continued for 12 weeks .
The Weight increase (W.I ), growth rate (G.R) , relative and specific growth rat ( RGR), food conversion ratio (FCR) , food conversion efficiency (FCE) , The results show that the best diet that provides maximum level of investigated measures, is that T2 there are significant differences between weight increase of fish with T1( control ) and T3. The highest ( FCR ) is 2.31 for diet T2, with ( FCE ) of 36.48 % ,There are no significant differences ( p < 0.05 ) in apparent digestibility between diets T1 with T3 and T2with T4 , and There are significant differences between T2 ,T4 with T1,T3 in all of studied Characteristics. Dry matter of the flesh of the experimented fish increased through increment of crude protein percentage which ranges between 13.73% and 14.76% , crude fat percentage which is ranges between 6.61and 6.91% while initially are 13.21 and 5.93% respectively.