Effects of dietary supplementation with glutamine on the lymphocyte proliferation and intestinal immune gene expression in broiler chickens infected with Salmonella Enteritidis

An experiment was conducted to investigate the effects of glutamine (Gln) on the lymphocyte proliferation and intestinal immune relevant gene expression in broilers infected with Salmonella Enteritidis. 240 1-day-old broilers were divided randomly into four groups in a completely randomized design, each of which had 6 replicates. Birds were reared in battery cages for 21 days. The experimental groups were as follows: control group (unchallenged group, CON), basal diet; Salmonella Enteritidis challenged group (challenged with 2.0 × 104 CFU/mL of Salmonella Enteritidis, SCC), basal diet; Gln 1, basal diet plus Salmonella Enteritidis challenged plus Gln at 0.5% diet; Gln 2, basal diet plus Salmonella Enteritidis challenged plus Gln at 1.0% diet. The results showed that Salmonella Enteritidis infection led to some decrease in the relative weight of spleen and bursa (except at 21 d), lymphocyte percentage, number of proliferation peripheral blood T and B lymphocytes, and increased the heterophil percentage, H/L ratio, mRNA expression levels of TNF-α, NF-κB p65, IL-1β, IL-6, and IL-8 in the jejunal and ileal mucosa compared with the measurements of these parameters in the CON group at d 4, 7, 14, and 21 (p