Effects of Glutamine on Digestive Function and Redox Regulation in the Intestines of Broiler Chickens Challenged with Salmonella Enteritidis

The aim was to investigate the effect of glutamine (Gln) on broilers challenged with Salmonella Enteritidis. 240 1-day-old birds were divided into four groups in a completely randomized design, each of which included 6 replicates with 10 birds per replicate. Group I served as the unchallenged, untreated control (CON). All birds in groups II (SCC) - IV were challenged with 2.0 x 10(4) CFU/mL of S. Enteritidis. Birds in group III and IV were treated with 0.5% (Gln 1) and 1.0% (Gln 2), respectively, of Gln. The results indicated that S. Enteritidis infection led to a decrease in the average body weight at d 7, 14, and 21 (p<0.05). Chickens fed the Gln showed improved average body weights in comparison with the SCC group (p<0.05). At d 4, 7, 14, and 21, the Gln groups increased digestive enzyme (trypsin, lipase and amylase (except the amylase activity of jejunum at d 14 and d 21)) activities in the intestine (p<0.05), superoxide dismutase (SOD) (at d 14 jejunum; except at d 4, ileum) and catalase (CAT) (at d 4, and d 21, jejunum; d 4, ileum) activity in the serum (except at d 14) and intestinal mucosa (p<0.05), and the mRNA expression of SOD, CAT and nuclear respiratory factor 2 (Nrf2) of the intestinal mucosa compared with the SCC group (p<0.05). These results suggest that Gln as a feed additive could be effective for reducing the detrimental effects of S. Enteritidis infection of broilers.