the effect of xylanase-protease enzyme supplementation in diets containing different levels of wheat on broiler chicken performance

non-starch polysaccharides (e.g.: wheat based diet) which are supplemented with enzymes. could have a high potential in nutrient ingestion, digestion and absorption, however, response to the enzyme is dependent on chicks age, as well as genetic status of both the cereal and the chick. this study was conducted in a completely randomized design in 2×4 factorial arrangement to study the efficiency of xylanase and protease enzymes with wheat based diet on broiler performance. one thousand and two hundred of commercial chicks (ross 308, both sexes) were randomly allocated into 8 dietary treatments with three replicates of 25 birds each. the diets were balanced separately for starter (1-10 d), female grower (11-24 d) and male grower (11-28 d), female finisher (25-49d) and male finisher (29-49 d) stages. the diets contained 0, 20, 35, and 50% wheat, replaced with corn, with or without enzyme. the enzyme containing diets 300-500 gr/ton of enzymes as well as all diets in each stage were isocaloric and isonitrogenous, fed ad libitum. body weight, feed consumption and feed conversion ratios were measured at the end of the growing period. two birds from each replicate were selected at the end of experiment, carcass weight, abdominal fat, excreta dry matter and pancreas weights were determined. the result indicated that weight gain, feed intake and feed conversion ratios were dramatically affected by different levels of wheat and enzyme supplementation (p> 0.05). there were significant differences observed among groups in carcass weight, percentage of abdominal fat and excreta dry matter (p> 0.05).