The effect of grape seed extract (GSE) feed supplementation on performance, antioxidant enzyme activity, and immune responses in broiler chickens suffering from heat stress were investigated in this study. Experimental diets including control diet (with no additive), 3 levels of GSE (150, 300, 450 mg/kg), and one level of vitamin C (300 mg/kg) as a positive control were fed to the birds from 1 to 42 d of age. The chronic heat stress (34±1 ˚C temperature for 5 hours per day) was provided from 29 to 42 d of age. The GSE supplementation up to 300 mg/kg diet increased the average daily gain of broiler chickens compared to the control group prior to heat stress (1-28 d). During the heat stress condition, dietary GSE at the rate of 300 and 450 mg/kg diet improved feed conversion ratio. The GSE supplementation at 300 mg/kg diet increased IgG titer as a primary and secondary response to sheep red blood cell (SRBC) injection. In addition, birds fed diet with GSE (150, 300, 450 mg/kg diet), or vitamin C (300 mg/kg diet) had higher levels of IgG titers as a secondary responses to SRBC. The GSE supplementation at the rate of 300 and 450 mg/kg diet reduced heterophil percent, heterophil/lymphocyte ratio, and increased the percentage of lymphocyte of broilers under heat stress. Supplementation of diet with GSE (300, 450 mg/kg diet) increased glutathione peroxidase (GPx) activity in birds under heat stress condition. The GSE or vitamin C supplementation did not affect the results of cutaneous basophil hypersensitivity (CBH) response, and relative weights of spleen and bursa of fabricius in chickens under heat stress. However, supplementation of diet with GSE (300, 450 mg/kg diet) or vitamin C (300 mg/kg diet) increased relative weight of thymus in birds under heat stress condition. Thus, GSE supplementation could alleviate the detrimental effects of heat stress in broiler chickens better than vitamin C and it is preferable for the health and economic goals since it is a natural waste by-product. تفاصيل المقالة

The main purpose of this study was to investigate the effect of different levels of fiber and fat on performance, pH, and viscosity of digesta in young broilers. A total of 420 one-day-old male chicks Ross 308 were assigned to 60 cages of seven birds each. The birds fed with 15 experimental diets produced by central composite design (CCD), containing three levels of sugar beet pulp (SBP: 0.00, 1.75, 3.50%), tallow (T: 0.00, 0.50, 1.00%) and soybean oil (SO: 0.00, 0.50, 1.00%) from 0 to 14 d. The results showed that maximum average daily body weight gain (ADG: 42.10 g/b/d) and minimum feed conversion ratio (FCR: 0.99) were observed with diet containing 0.35% SBP, 0.00% T and 0.51% SO. Maximum (4.64) and minimum (3.01) pH in gizzard were found with diets containing 0.00% SBP, 0.51% T, 0.27% SO and 1.70% SBP, 0.21% T and 0.00% SO, respectively. The highest (6.94) and lowest (5.86) pH in ileum contents were obtained with diets comprising 0.00% SBP, 1.00% T, 0.43% SO and 1.47% SBP, 0.00% T, and 0.00% SO, respectively. Maximum (3.54) and minimum (1.50) viscosity in ileal digesta were observed with diets containing 3.50% SBP, 1.00% T, and 1.00% SO and 0.00% SBP, 0.00% T and 0.53% SO, respectively. This experiment has revealed that, the CCD and response surface methodology (RSM) have the efficiency to describe the relationships between different levels of SBP, T and SO and the ability to predict the optimal point of the level of diet ingredients in order to achieve the best performance. With increasing the amount of SBP and decreasing the level of T and SO in the diets, the pH of digesta in the gizzard and ileum decreased. The ileum digesta viscosity increased with increasing SBP, T, and SO levels. تفاصيل المقالة

This experiment aimed to evaluate the effects of probiotic administration route (PAR),dietary nutrient density (DND) and Eimeria challenge (ECH) on performance, gut morphology, and hematological variables in broiler chickens. Eggs carrying 17.5-day-old broiler embryos were injected with 0.1 mL distilled water (vehicle control) or 0.1 mL distilled water containing probiotic. A group of 72 intact eggs was also included in the experimental design representing un-injected control. Hatchlings from intact and probiotic injected eggs were further evaluated in a 42-d floor-pen trial along with 465 additional hatchmate chicks. Chicks were placed in two environmentally controlled houses, each having 30 floor pens randomly assigned to the following six treatments: conventional chicks receiving a standard diet with (group 1) or without (group 2) probiotic; conventional chicks receiving a 5% diluted diet with (group 3) or without (group 4) probiotic; and in ovo probiotic-administered chicks receiving standard diet (group 5) or 5% diluted diet (group 6). All birds in one of the houses were inoculated with a pathogenic dose of an attenuated live Eimeria vaccine at 28 d. Chicks receiving in ovo probiotic showed reductions in hatch weight and yolk sac weight compared to control (P<0.05); the same group, however, had a significantly higher weight gain (WG) during the first 10 days post-hatch but this improvement disappeared with age. Groups receiving standard diet exhibited better growth performance than those fed the 5% diluted diet. Eimeria challenge caused significant adverse effects on performance traits, intestinal morphology, and hematological variables. It is concluded that neither PAR nor DND could alleviate Eimeria induced deteriorations in productivity and health of broiler chickens. تفاصيل المقالة

This experiment was conducted to assess the effect of three levels of dietary sugar beet pulp (SBP), tallow (T) and soybean oil (SO) on the performance and morphology of the jejunum in the young broilers were applied central composite design (CCD; 3 levels and 3 factors) and response surface methodology (RSM). A total of 420 one-day-old male chicks Ross 308 were appropriated to 60 cages of seven birds each and fed with 15 diets, produced by CCD containing three levels of SBP (0.00, 1.75, 3.50%), T (0.00, 0.50, 1.00%) and SO (0.00, 0.50, 1.00%) from 0 to 14 days of age. The results showed that maximum average daily body weight gain (ADG, 31.59 g/bird/d) and minimum feed conversion ratio (FCR, 1.02) were obtained with diets comprising 0.51% SBP, 0.20% T, 0.38% SO and 0.50% SBP, 0.05% T and 0.10% SO, respectively. On day 7 of age, the linear effects for all models, the quadratic and interactions effects for the number of goblet cells (GC) model were significant (P<0.05). On day 14 of age, the linear and quadratic effects for all models and the interactions for the model of villus width (VW) were significant (P<0.05). Generally, aging and subsequent growth and expansion of the gastrointestinal tract can moderate the destructive impacts of soluble fibers to some extent and the RSM could provide an acceptable prediction for the relevance between variables and traits. تفاصيل المقالة