Effect of dietary dried orange (Citrus sinensis) peel powder and exogenous multi-enzymes on growth and carcass traits and ileal microflora of broiler chickens

The effects of dietary inclusion of dried orange peel powder (OPP) and supplementation of a commercial multi-enzymes (Natuzyme P50®) on the growth and carcass traits, gastrointestinal tract size and ileal microflora of meat-type broiler chickens were evaluated. Broiler chicks were assigned to treatments according to a completely randomized design by adding different levels of dried OPP (0, 1 and 4 g/kg, respectively) and multi-enzymes (0, 350 and 700 ppm, respectively) and their combination. On day 42, birds were slaughtered and samples collected. Growth traits varied marginally among dietary groups; however, multi-enzymes inclusion appeared to improve broilers weight gain without affecting feed efficiency. Dietary treatments did not affect the immunity-related organs weights. The multi-enzymes inclusion led a significant improvement of the gastrointestinal tract size as well as of gut microflora markers. In overall, our findings suggest that the inclusion of multi-enzymes in diet appeared to improve broilers performance; whereas supplementing dried orange peel powder has no effect.