Abstract: The experiment was aimed to study the influence of Glutamine and Glycylglutamine supplementation on growth performance and immunity organ growth of Yellow-feathered Broilers. 90 Yellow-feathered Broilers at one day old were randomly divided into three groups with three repetitions and 10 Yellow-feathered Broilers each: one group was fed the basal diet as control group, and other groups were fed the basal diet supplied with 0.40% Glutamine and 0.20% Glycyl-glutamine. The trial lasted for 28 days. The results indicated that supplemental 0.40% Glutamine or 0.20% Glycylglutamine could enhance average daily gain and the growth immunity organ including Thoracic gland,Spleen,Bursa of Fabricius of Yellow-feathered Broilers. Supplemental 0.20% Glycyl-glutamine could significantly (P<0.05) increase average daily gain in the period of 1~7 d and the Bursa of Fabricius index on day 28 of the experiment. Supplemental 0.20% Glycyl-glutamine and 0.40% Glutamine had the same influence in enhancing the growth performance and the growth of immunity organ.

Key words: glutamine; glycyl-glutamine; daily gain; immunity organ