Effects Of Chitosan On Growth Performance And Immune Function In Piglets

The present study was conducted to determine the effects of chitosan on growth performance, immune function, metabolic rate of nutrients and the level of endocrine hormone of piglets by feeding trial and metabolism trial.A total of 96 piglets at the age of 60 days were randomly divided into 4 treatments, each treatment consisted of 3 replicates with 8 piglets. The four treatments were fed the basal diet supplemented respectively with 0, 0.01%, 0.05%, 0.1% chitosan. The experiment lasted for 21 days. The results showed that chitosan improved growth performance in a quadratic dose-dependent manner, and the supplementation of 0.01%~0.05% chitosan to the diet increased average daily gain (ADG), average daily feed intake (ADFI) and the ratio of gain to feed intake (G/F). However, the addition of 0.1% chitosan to diet gave negative effects on performance. Chitosan had dose-dependent effects on the rat of diarrhea in piglets; the addition of 0.01%~0.05% chitosan to diet could inhibit the rat of diarrhea in piglets.On d 7, 14 and 21 of the feeding trial, T lymphocyte proliferation rate, ovalbumin (OVA) antibody, the contents of IgG, IgM, IgA, IL-1 and IL-2 in serum was analyzed. The results showed that chitosan promoted lymphocyte proliferation and serum OVA antibody, and the best dosage was 0.05%. Chitosan also improved the serum IgG, IgM, IgA, IL-1 and IL-2, and the best dosage was 0.01%～0.05%. These results indicated that diets supplemented with 0.01%～0.05% chitosan improved cellular immunity and humoral immunity function in piglets.On d 7, 14 and 21 of the feeding trial, the serum IGF-I, GH and cortisol (Cor) were analyzed, so as to study the mechanism of improving growth performance from endocrine. The results showed that the effects of chitosan on serum levels of GH and IGF-I in piglets was related to dosage , and the addition of 0.01%～0.05% chitosan to diets increased serum levels of GH and IGF-I. In addition, dietary chitosan could depress the serum level of Cor.The metabolism trial adopted 8 boars at the age of 60 days and lasted for 28 days. The design of experiment was 4×4 Latin square. This trial was conducted to explore the effects of chitosan on nutritive substance metabolism in piglets. The result showed the addition of 0.01%～0.05% chitosan to diets increased the apparent metabolic rate of crude protein, Ca and P, but there was no significant effect to the apparent metabolic rate of crude fat and energy.