عنوان مقاله [English]
نویسندگان [English]چکیده [English]
An experiment was conducted to investigate the effect of wheat screenings with and without enzyme preparation on the performance, gastrointestinal parameters and gut viscosity and morphology of broiler chicks during grower period (11 to 24d). Five hundred day old male broiler chicks were fed a commercial diet till 10 d of age and then were randomly assigned to 10 diets. Diets were formulated to have five different levels (0, 9, 18, 27 and 36%) of wheat screenings with or without enzyme. Each diet fed to five groups of ten male birds. There was no significant difference in feed intake (FI) and feed conversion ratio (FCR) of chickens fed diets with different levels of wheat screenings during 14 days of age. Body weight gain (BWG) was decreased significantly with increasing level of wheat screenings in diets. Enzyme supplementation significantly increased BWG and decreased FCR. Increasing wheat screenings level significantly decreased gastrointestinal tract weight including pancreas, gizzard, large intestine as well as liver. Enzyme supplementation significantly decreased weight of liver, proventriculus, gizzard, pancreas, and large intestine. Villi height was decreased significantly by increasing wheat screenings level. Carcass weight was not affected by wheat screenings level and enzyme. Ileum and jujenum digesta viscosity increased by wheat screening level and decreased by enzyme supplementation. Increasing wheat screenings level increased villi width and decreased villi height and crypt depth. Enzyme supplementation increased villi height and crypt dept. Histological observations on jejunum of birds fed wheat screenings without enzyme showed shortening, thickening, and atrophy of the villi, all of which improved when enzyme was included in the diet.