This study was carried out to evaluate the effect of sodium butyrate (SB) as a feed additive on the intestinal immune response against Eimeria maxima infection and histomorphological structure of intestine of broiler chickens. One-hundred-day old broiler chicks were divided into 4 groups, 25 per each. 1st group was fed on normal diet only. 2nd group was fed on normal diet and infected with 1.0 ml of a solution containing 5.0 × 103 sporulated oocysts of E.maxima on the 22nd day of age. 3rd group was fed on normal diet + SB (1gm/kg feed) and infected as group two.4th group were fed on normal diet + SB (1gm/kg feed). Five birds from each group were euthanized on the 5th, 10th, and 15th days post-infection and blood and tissue samples were collected to evaluate the difference in jejunum and ileum histopathology and determination of inflammatory cytokines in serum. Results revealed significant increase in intestinal villi length and crypt depth in treated group compared to control group. SB has significantly increased the intestinal immunity against E.maxima infection, there was decreases in number of coccidial stages within the mucosal lining in infected treated groups compared to infected non-treated groups, there was decrease enteritis feature with noticeable intestinal regeneration in group 3 compared to group 2 that showed necrotic enteritis associated with sever sloughing of the epithelial lining. SB modulated the expression of immune related genes in term of increased in IL-10 and decrease (IL-1β &INF-γ) genes expression. |