Compare the effect of diet supplementation with uncoated or coated lysine on juvenile Jian Carp (Cyprinus carpio Var. Jian)

This study was designed to determine the effects of diet supplementation with uncoated lysine (UCL) or coated lysine (CL) to juvenile Jian carp Cyprinus carpio Var. Jian. 330 juvenile Jian carps (initial weight 7.89 ± 0.04 g) were randomly allocated to two groups, feeding a diet containing UCL or a CL for 80 days. Weigh gain, feed intake and feed efficiency ratio were higher in group CL than group UCL, indicating the effect of CL to be better than UCL. Hepatopancreas weight and protein content, intestinal weight, length and protein content, intestinal folds height, activity of intestinal protease, lipase, alkaline phosphatase (AKP), Na⁺, K⁺-ATPase were positively affected by CL. Moreover, glutamate-oxaloacetate transaminase (GOT) in muscle, and plasma ammonia, tended to be lower for CL, which means that the improvement of digestive organ development and function may be the possible reason why CL was better than UCL.