An experiment was conducted to study the effects of enzyme and phytogenic product (thymol+carvacrol) on the ileal microbial population and jejuna and ileal histomorphology of broilers fed wheat based diet. The experiment was conducted as a 2 × 3 factorial arrangement with 2 levels of enzyme endofeed W (0 and 0.05%) and 3 levels of next enhance 150® (0, 100 and 200 mg/kg). Each of the 6 dietary treatments was fed to 5 replicate pens (12 birds/pen) from 0 to 24 d of age. Adding enzyme and phytogenic product into wheat based diet increased (P<0.05) Lactobacillus and decreased (P<0.05) E. coli population while it had no ef-fect on Bifidobacterium when compared to the control group. For jejunal histomorphology at d 24, addition of enzyme into wheat based diet increased (P<0.05) villus height (VH), villus surface (VS), crypt depth (CD), mucosa layer thickness (MCL) and goblet cell (GC) although villus width (VW) decreased (P<0.05) when compared to the control group. Pytogenic product supplementation significantly increased VH, VS, villus height to crypt depth (VH:CD) and GC but it was not significant for CD, MCL and mascular layer (MSL). Results of jejunal measurement showed that enzyme supplementation increased (P<0.05) VH, CD, MCL and GC although decreased (P<0.05) VW in contrast with control group: enzyme increased ileal VH, VS and GC at 24 days of age, but VW, CD, MCL and MSL was not affected by that. Effect of thymol + carvacrol on ileal morphology at d 24 followed the similar pattern of enzyme addition. At d 42, ileal meas-urement showed that enzyme supplement significantly enhanced VH and CD and thymol + carvacrol in-creased VH and VS. Thus, the addition of enzyme and phytogenic product can modify microbial status of intestinal by increasing beneficial microbial population, decreasing pathogens and improve mucosa struc-ture of jejunum and ileum by increasing villus height, villus surface area and goblet cell.

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