Abstract: The experiment was conducted to study the effects of glutamine replacing antibiotics in diet on immune organ indexes and intestinal mucosal immune function of the Yellow broilers. One hundred eighty Yellow broilers with similar weight and good health for one day old were randomized into two control groups and three trial groups with 3 replicates per group and 12 chickens per replicate. The positive control group was fed with diet supplemented with 0.3 g/kg nosiheptide and 0.25 g/kg colistin sulfate premix,negative control group was fed with basal diet,the trial Ⅰ,Ⅱ and Ⅲ groups were fed with diet supplemented with 1,2,3 g/kg glutamine,respectively. The results showed that compared with the positive and negative control groups,the immune organ weight and indexes of trail Ⅰ,Ⅱ and Ⅲ groups were all not significant, respectively,and the difference among the experimental groups were also not significant. On 45 d lysozyme content in the duodenum,jejunum mucosa protein of broilers in treatment Ⅰ and Ⅱ groups decreased compared with the positive control group(P＞0.05). The bacteria content of trialⅠ,Ⅱ and Ⅲ groups and the negative control group in duodenal were higher than the positive control group(P＜0.05). On 77 d lysozyme content in duodenum,jejunum,ileum mucosa protein of treatment Ⅰ,Ⅱ and Ⅲ groups had no differences compared with the positive control group(P＞0.05).The SIgA content in duodenum was lower than the negative control and the positive control groups. Acetic acid,propionic acid,and total acid concentrations in ileum content of the treatment groups were lower than the positive control group and higher than the negative control group.Therefore,glutamine substitution for antibiotics feed additive seemed to improve cellular immunity and mucosal immunity in intestine of Yellow broilers.

Key words: glutamine; feed antibiotic; Yellow broilers; immune organ index; intestinal mucosal immune