effect of different levels of the amino acid lysine on growth, feed efficiency and body composition of juvenile snow trout (schizothorax zarudnyi

abstract this study aimed to investigate the effects of different levels of the amino acid lysine on growth performance, feed efficiency and body composition of juvenile snow trout (schizothorax zarudnyi). for this purpose, 150 fish with average weight 22.51±0.28 g fed with five levels of dietary amino acid lysine including 0 (control), 7, 12, 17 and 22 g/kg diet, for 8 weeks. fish fed two times daily at 3% body weight rate. at the end of feeding trial, growth performance, feed efficiency and body composition were recorded. maximum final weight and body weight, best average daily gain, best specific growth rate and increase the relative weight were evident for 17 g/kg diet treatment. maximum body protein content was obtained for 17 g/kg diet treatment. body moisture, fat and ash content remained unchanged. based on the above results, it may be concluded 17 g lysine per kg diet is optimal for the growth, feed efficiency and body composition of juvenile s. zarudnyi.