Effect of Antibiotic Alternatives on Ileal Microflora and Intestinal Histomorphology of Broiler Chickens Fed Wheat Based Diet

Abstract

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) <em>Lactobacillus</em> and decreased (P<0.05) <em>E. coli</em> population while it had no effect on <em>Bifidobacterium</em> 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 measurement showed that enzyme supplement significantly enhanced VH and CD and thymol + carvacrol increased 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 structure of jejunum and ileum by increasing villus height, villus surface area and goblet cell.