Influence of glutamine and vitamin E on the performance and the immune responses of broiler chickens

Abstract

This study aimed at evaluating the influence of Glutamine (Gln) and Vitamin E (VE) supplementation on the performance and immune response of broilers. A completely randomizes experimental design with a 2 x 3 (VE x Gln) factorial arrangement was used. VE was supplemented at 10 and 500 mg/kg feed, with or without Gln (1%) addition, and two periods of supplementation in the starter diets (1-7 and 1-14 days of age), with five replicates of 50 birds each. The analyzed parameters were: live performance (weight gain, feed intake, and feed conversion ratio); relative weights of the spleen, bursa, and thymus; antibody titers (with sheep red blood cells suspension - SRBC) and cutaneous basophilic hypersensivity (CBH). Data were submitted to the analysis of variance, and means were compared using the test of Tukey. Treatments did not influence (P>0.05) live performance parameters or antibody titers. VE reduced (P=0.01) CBH, with the level of 10 mg VE/kg allowing higher cell proliferation as compared to 500 mg VE/kg. As to lymphoid organs, only the spleen was affected (P=0.035) by Gln, which resulted in higher spleen relative weight when fed during the first week of age. Results showed that 10 mg VE/kg with Gln (1-7 days) promoted better immune responses.