Improved performance and small intestinal development of broiler chickens by dietary L-glutamine supplementation

Abstract

An experiment was conducted to evaluate the effect of L-glutamine (Gln) supplementation on performance and intestinal morphology of broiler chickens. A total of 192 day-old male broilers (Ross 308) were used in a completely randomised design with four treatments and four replicates of 12 birds each. Four experimental diets were formulated to be isonitrogenous and isocaloric with different levels of Gln supplementation (0, 0.5, 1.0 and 1.5%) in control and treatment groups, respectively and were fed for the first 3 weeks of life. On days 21 and 42, one bird from each replicate was slaughtered and morphometric indices of the small intestine were evaluated. Results obtained on days 21 and 42 showed increased ADWG in the birds that consumed 1% Gln supplemented diet compared to the control birds fed a standard corn-SBM diet (P≤0.05). On day 21, birds fed diets supplemented with 1 or 1.5% Gln had a significantly heavier duodenum and jejunum relative weight compared to the control birds (P≤0.05). Morphological assays showed that villus height and villus surface area of the duodenum and jejunum were significantly increased at both 21 and 42 days of age, as 1 or 1.5% Gln was supplemented in broiler diets (P≤0.05). The results of this study indicated that addition of 1% Gln to the diet for 21 days improved growth performance and small intestinal development of broiler chickens at the end of the starter (day 21) and grower (day 42) period.