Effect of Dietary Chitosan on Growth Performance,Lipid Metabolism,Non-Specific Immune Function and Intestinal Health of Juvenile Jian Carp(Cyprinus carpio var.Jian)

This experiment was conducted to investigate the effects of chitosan oligosaccharides on growth performance,lipid metabolism and non-specific immune function and intestinal health of juvenile Jian carp(Cyprinus carpio var.Jian).A total of 225 juvenile Jian carp with an average body weight of(8.78±0.38)g were randomly divided in 5groups with 3replicates per group and 15 fish per replicate.The fish in the 5groups were fed the diets supplemented with 0(control group),0.3%,0.6%,0.9% and 1.5% of chitosan oligosaccharides for 80 days,respectively.The results showed as follows:compared with the control group,specific growth rate and weight gain rate in different chitosan oligosaccharides groups were increased(P0.05);plasma triglyceride and total cholesterol contents of 0.6%group were significantly lower than those of other groups(P0.05),while plasma high density lipoprotein cholesterol content was significantly higher than that of other groups(P0.05);plasma malondialdehyde content of each chitosan oligosaccharides group was significantly lower than that of control group(P0.05),and plasma total antioxidant capacity of 0.6% group was significantly higher than that of control group(P0.05);the phagocytic rate of leukocyte and intestinal fold density of each chitosan oligosaccharides group were significantly higher than those of control group(P0.05),and intestinal wall thickness of 0.6% and 0.9% groups was significantly bigger than that of control group(P0.05);the amount of Escherichiacoliin intestine of chitosan oligosaccharides group was significantly lower than that of control group(P0.05),while the amounts of Bifidobacterium and Lactobacillus in intestine of 0.6% and 0.9% groups were significantly higher than those of control group(P0.05).Collectively,these findings suggest that the chitosan oligosaccharides can improve growth performance and non-specific immune function,and adjust lipid metabolism of juvenile Jian carp.According to the Xextreme value analysis of regression curves of non-specific immunity and intestinal health,it can be concluded that the optimal supplemental level of chitosan oligosaccharides in the diet of juvenile Jian carp is 0.86%to 1.09%.