The effect of high dietary inclusion of distillers dried grains with solubles, enzyme supplementation and necrotic enteritis challenge on gut microflora and immune response of broiler chickens

Gut microbial profile and serum immunoglobulin were studied in a 2x2x2 factorial experiment investigating dietary effect of sorghum distillers dried grains with solubles (DDGS) (0 vs. 200 g/kg), with or without protease and xylanase in broiler chicks under necrotic enteritis (NE) challenge. Each of 8 experimental treatments was replicated 6 times (12 birds per cage). Microbial plate counting was performed for the ileal and caecal digesta (d 13 and 17) before and after 'Clostridium perfringens' ('C.p.') inoculations. Total serum IgA, IgG and IgM were detected on d 13, 21 and 35. On d 17, infected birds had a higher number of ileal coliform, lactic acid bacteria, lactobacilli and total anaerobes, while birds fed diets containing DDGS had lower total anaerobes. Inclusion of DDGS increased the proliferation of 'C.p.' in caeca at d17 with an interaction between challenge and DDGS. Showing the same interaction, inclusion of DDGS in the diet decreased IgG at d 21 and IgM at d 35 in the infected birds. Enzymes had no effect on the parameters assessed except an increase in IgA titre at d 21. To conclude, high dietary inclusion of DDGS may increase susceptibility of broiler chickens to NE.