Effects of different types of antimicrobial lipopeptides supplementation on weight gain rate，serum biochemical indexes and non-specific immune ability of GIFT strain of nile tilapia（Oreochromis niloticus）

A 7-week feeding trial was conducted to evaluate the effects of different types of antimicrobial lipopeptides supplementation on the weight gain rate，serum biochemical indexes and non-specific immune ability of genetically improved farmed tilapia（GIFT，Oreochromis niloticus）. 240 fishes with initial average weight of 2.01（± 0.03）g were randomly divided into four treatment groups with four replicates in each treatment group and 15 fishes in each replicate. Results showed that，compared with control group，weight gain rate，albumin level，lysozyme activity， and levels of immunoglobulin M and complement 3 in serum significantly increased by different types of antimicrobial lipopeptides supplementation，the levels of urea nitrogen，total cholesterol，triglyceride and low density lipoprotein cholesterol in serum significantly decreased. The high density lipoprotein cholesterol level，glutamic-oxalacetic transaminease activity and glutamic-pyruvic transaminase activity were not affected by different types of antimicrobial lipopeptides supplementation. The above parameters of antimicrobial lipopeptides supplementation groups were similar. In conclusion，different types of antimicrobial lipopeptides might have the similar effect on growth promotion and improvement of serum biochemical indexes and non-specific immune ability of GIFT tilapia under present experimental condition.