Effect of various levels of dietary carbohydrate on growth parameters and body chemical analysis of Snow trout juveniles (Shizothorax zarudnyi)

In this study investigated the effect of different levels of carbohydrate in artificial diets on growth parameters and body chemical analysis of Snow trout juveniles (Shizothorax zarudnyi) in 8 weeks. Hundred fifty Snow trout juveniles with average weight 3.54±1.14 g and length 8.5±2.4 cm fed with five isonitrogenous and isolipidic diets and varying levels of carbohydrates (16.59%¡ 22.2%¡ 26.99%¡ 32.9% and 36.77% ). Ten advanced fry were stocked into each 45-l aquaria with triplicate in five treatments and fed twice daily at 5% body weight rate. Results indicated highest body weight gain (2.83±0.02)¡ specific growth rate (1.05±0.03)¡ average daily gain (5.06±0.05)¡ protein efficiency ratio (0.71±0.01) ¡ feed efficiency ratio (0.25±0.01) and lowest feed conversion ratio (3.94±0.04) observed in D4 treatment that fed by diet containing 32.9% carbohydrate that no significantly difference with D5 treatment that fed by diet containing 36.77% carbohydrate while significantly differences with other treatment (p˃0.05). Also there were no significant differences in wet and ash demand of carcass treatment fed by various levels of dietary carbohydrate¡ while lipid and protein in carcass in treatment that fed by diet containing 32.9% and 36.77% carbohydrate increase and decrease respectively (p˃0.05). Finds of this study indicated that best containing diet carbohydrate for optimal growth and nutrition indexes in Snow trout juveniles is 32.9% to 36.77%.