Effects of Glutamine Supplementation on Broiler Performance and Intestinal Immune Parameters During an Experimental Coccidiosis Infection

Abstract

SUMMARY: The objective of this study was to evaluate the effects of glutamine supplementation on performance and intestinal immune parameters of broilers during an experimental coccidiosis infection. There were 3 glutamine supplementation levels in this study: 0, 0.5, and 1.0%. At 14 d of age, each bird was given an oral gavage of 20X dose of Coccivac B52 suspended in distilled water. IFN-γ mRNA levels were downregulated 11.8- and 2.0-fold in the jejunum and 8.1- and 7.9-fold in the cecal tonsils of birds supplemented with 0.5 and 1.0% glutamine at 21 d, respectively, compared to that in the birds fed 0% supplemental glutamine (P = 0.06 and P = 0.01, respectively). At 21 d of age, IL-10 mRNA levels were downregulated in the jejunum of the birds supplemented with 0.5 and 1.0% having a 25.3- and a 1.5-fold lower level, respectively (P 0.05) were observed on any performance parameter or T-cell population percentages. This study shows that glutamine supplementation upregulated tight junction protein gene expression, improved intestinal morphology, and downregulated pro- and anti-inflammatory cytokine gene expression. In conclusion, these results indicate that dietary glutamine supplementation can improve intestinal health in birds challenged with an experimental coccidiosis infection.

Keywords

• glutamine
• broiler
• coccidiosis