Study On Chitosans With Different Desacetylated Degree In Broiler Diets

Chitosan is the only edible animal fiber with cation in the nature. It is called a type of new additives which has the effectiveness of antibiotic activity, antivirus activity, adjusting metabolism of fat, improving immunity and so on. The experiment was conducted to study the effect of the different desacetylated degree of chitosan on performance, abdominal fat and blood fat, immunological function and intestinal microbial by feeding trial, slaughter trial and intestinal microbial trial.In the experiment, 250 Arbor Acre broilers(1d of age)were randomly divided into five groups, with five replications per group. The control group(Group I)was fed with corn-soybean meal basal diet, the trial groups(Group II, III, IV and V)with basal diet plus 10g/kg chitosan with desacetylated degree of 82.5%, 86.2%, 90.5% and 95.3%, respectively. Experimental period is seven weeks. At 21d, 35d and 49d, weights, gains and feed intakes of every replication were weight and average daily gains, feed intakes and feed efficiency were calculated; blood samples were obtained from one broiler of each group to measure T lymphocytes percentage, HI titers, CHOL, TG, HDL-C, LDL-C, IgA, IgG, IgM in serum and indexes of immune organs of Thymus gland, Bursa of Fabricius and spleen; fresh caecum were collected and assayed immediately for Escherichia coil, Lactobacill, Bifidobacterium and pH content. The result showed thatFrom 1 to 49 day, daily gains of groups were 47.37g, 9.08g, 47.74g, 46.38g, 49.38g, chitosan groups had no effect on growth performance of young broilers during the whole growing stage. During 1d to 21d age, daily gains of groups were 27.09g, 26.79g, 24.56g, 25.93g, 25.66g, chitosan groups decreased growth performance, and chitosan with desacetylated degree of 86.2% group decreased growth performance compared with chitosan with desacetylated degree of 82.5% group and the control group(p<0.05). During 22d to 49d age, daily gains of groups were 62.77g, 65.80g, 65.13g, 61.72g, 67.00g, chitosan supplement had no difference on growth performance of young broilers.Chitosan with different desacetylated degree can decrease fat rate and blood fat, but had no significant difference (p>0.05).Chitosan groups had no difference on indexes of thymus gland, Bursa of Fabricius and spleen. Chitosan supplement improved T lymphocytes percentage. In 21d age, chitosan with desacetylated 86.2% degree improved T lymphocytes percentage than control group(p<0.05), other chitosan groups were no significant difference (p>0.05). In the whole growing stage, chitosan supplement...