Effects of chitosan on growth performance, antioxidant status and some hematological and biochemical parameters of broilers

Chitosan is one of the derivatives of marine crustacean chitin shells and a polymer of glucosamine, which is obtained from the deacetylation of chitin. The biological activities of chitosan, such as its cholesterol-lowering effects, as well as its antibacterial and antioxidant effects, are well known in some species. Therefore, this experiment was performed to investigate the effects of chitosan on antioxidant status and some biochemical parameters in broiler chickens. For this study, 400 male broilers of Ross 308 strain were assigned to four treatments, five replications, and 20 chickens for each replication in a completely randomized design. Experimental treatments included 1) basic diet, and treatments 2, 3, and 4) were levels of 0.5, 1, and 2 g of chitosan per kg of basic diet, respectively. Blood and biochemical parameters including red blood cell count, white blood cell count, hemoglobin content, hematocrit, monocyte, heterophils and lymphocyte count, triglyceride and blood cholesterol, antioxidant enzyme activity including glutathione peroxidase, superoxide disodium, and peroxidase Plasma hepatic enzymes alanine aminotransferase and aspartate aminotransferase were measured. Growth performance parameters including weight gain, feed intake and feed conversion ratio were also calculated for the whole experimental period. The results showed that different levels of chitosan significantly improved the antioxidant indices by increasing the activity of antioxidant enzymes (glutathione peroxidase, superoxide dismutase, and catalase) and reducing the levels of alanine aminotransferase and aspartate aminotransferase enzymes. Growth performance parameters and other blood parameters except white blood cell count were not significantly affected by different levels of chitosan. The use of chitosan significantly improved antioxidant parameters (increasing the activity of antioxidant enzymes and simultaneously decreasing the level of liver enzymes) in broilers. Therefore, the use of proposed chitosan levels in this scheme is recommended to improve the antioxidant status of broilers in conditions of oxidative stress.