Effect of yeast-derived products and distillers dried grains with solubles (DDGS) on growth performance and local innate immune response of broiler chickens challenged with Clostridium perfringens

This study evaluated the effect of yeast-derived products on growth performance, gut lesion score, intestinal population of Clostridium perfringens, and local innate immunity of broiler chickens challenged with C. perfringens. One-d-old broiler chickens were randomly assigned to 8 dietary treatments providing 6 replicate pens of 55 birds each per treatment. Dietary treatments consisted of Control diets without and with C. perfringens challenge, and diets containing bacitracin methylene disalicylate (BMD, 55 g/tonne), nucleotides (150 g/tonne), yeast cell wall (YCW, 300 g/tonne), and a commercial product Maxi-Gen Plus (1 kg/tonne) fed to chickens challenged with C. perfringens. Diets containing 10% DDGS without and with C. perfringens challenge were also used. Birds were orally challenged with C. perfringens (10(8) CFU/bird) on d 14. On d 21, intestinal samples were collected for gene expression analysis. Pathogen challenge significantly (P<0.05) impaired feed intake, body weight gain, and FCR shortly after the challenge (14-21d). Increased C. perfringens counts and intestinal lesion score were observed for challenged birds except the BMD-containing diet. Over the entire trial (1-35d), no difference in growth performance was observed except the BMD diet which improved FCR over the Control, challenged group. Birds receiving nucleotides showed increased expression of toll-like receptors and cytokines interleukin (IL)-4 and IL-18 compared to the Control, challenged group. Expression of macrophage mannose receptor and IL-18 was upregulated in birds receiving YCW. Increased expression of cytokines and receptors involved in innate immunity in broilers receiving nucleotides and YCW suggests the immunomodulatory properties of these products under pathogen challenge conditions.