Dietary supplementation of glutamine and glutamic acid on performance, intestinal morphometry, and carcass characteristics of broiler quails

Abstract

ABSTRACT: This study evaluated the effect of dietary supplementation with glutamine and glutamic acid (Gln+Glu) on performance, intestinal morphometry, and carcass characteristics of broiler quails. Eight hundred birds were used, distributed in an entirely randomized design with 20 birds per experimental unit, and given five treatments (0.0; 0.2; 0.4; 0.6; and 0.8% Gln+Glu supplementation) with eight replicates. At 1-21 days of age, lower (P < 0.05) feed intake at 0.6 and 0.8% Gln+Glu supplementation and lower weight gain at 0.8% Gln+Glu supplementation compared to the control treatment were observed. By regression analysis, excluding the control treatment, there was an increasing linear effect (P < 0.05) for feed intake at 22 to 42 days of age. For intestinal morphometry, Gln+Glu supplementation only favored the villus development of the ileum (P < 0.05), giving it greater height at 0.2, 0.6, and 0.8% supplementation. Carcass characteristics, cuts, and edible viscera of the birds at 42 days were not affected (P > 0.05) by Gln+Glu supplementation levels. Thus, the glutamine and glutamic acid supplementation affected the performance and intestinal morphology of 21-d-old quails, decreasing feed intake and weight gain associated with the improvement of ileum morphology; conversely, performance and carcass characteristics at 42 days were not affected by amino acid supplementation.