عنوان

بررسی اثرات افزودن پروبیوتیک و آنزیم بر عملکرد رشد، صفات لاشه، عملکرد سیستم ایمنی هومورال و برخی از فراسنجه های خونی جوجه های گوشتی در جیره‌های غذایی بر پایه گندم و کنجاله سویا

Text of Note

Abstract:The aim of this study was to investigate the effects of probiotic and enzyme on growth performance, carcass traits, humoral immune response and blood biochemical parameters of broiler chickens fed wheat-soybean meal-based diets. In total, 240 day-old Ross 308 chicks were allocated in a completely randomized design including 6 treatments, 4 replicates and 10 birds per each and experimental diets were fed for 6 weeks. Experimental diets were: 1- Wheat-soy bean meal based diet as control groupe, 2- Control diet with supplemented enzyme (250 mg / kg diet), 3- Control diet with supplementation of probiotic -(100 mg/kg diet)., 4- Control diet with supplementation of oxytetracycline (OTC) (200 mg / kg of diet), 5- Control diet with supplementation of enzyme and probiotic -and 6- Control diet with supplementation of OTC and enzymes. The birds had free access to water and food during the whole experimental period, and all management activities such as lighting program and house temperature were done based on the Ross 308 management guide recommendation.. Growth performance traits including average daily feed intake, daily weight gain were recorded periodically (starter: 0-10 d, grower: 11-24 d, finisher: 25-42 d) and feed conversion ratio was also calculated. To study the carcass traits at the end of the experimental period on day 42, one male bird was randomly selected for each replicate and humanely sacrificed after 8 hours of fasting, and the carcass traits were expressed as a proportion of body weight. At 42 d, blood biochemical parameters of broilers including :glucose, triacylglycerol, cholesterol, LDL, HDL, calcium, phosphorus, aspartate aminotransferase (AST) and alanine aminotransferase( ALT), total protein, globulin and albumin were measured. data were collected, sorted, and checked the normality, and then were analyzed by using SAS statistical software and GLM procedure and the results were reported (P <0.05). The results showed that the highest average daily weight gain in the whole experimental period (0-42 days) were observed in chickens fed antibiotics and enzymes (66.77 g / day) and the lowest one were seen in chickens received probiotic (60.69 g in Day). The lowest feed conversion ratio was observed with addition of enzyme alone and the addition of enzyme plus antibiotic.The effect of adding probiotic and enzyme on the relative weight of breast, drum stick, gizzard, pancreas, giblet, and percentage of broiler carcasses was significant (P <0.05). The highest percentage of carcass yeild was observed in broilers received antibiotic, enzyme, and probiotics. Experimental treatments did not significantly affect the pH of different segments of the gastrointestinal tract. The results of the relative weight of small intestine segments showed that broilers that fed probiotic had the highest relative weight and diets containing probiotics and enzymes had the lowest weight. The results indicate that the relative length of the duodenum is highest in broilers fed a probiotic diet. The total protein concentration of broiler chickens fed a probiotic diet is the highest. The relative weight of the lymphoid organs was not affected by the dietary treatments. Experimental treatments had a significant effect on heterophils and the ratio of heterophils to lymphocytes (H/L) (P <0.05). The effect of experimental treatments on antibody titer against sheep red blood cells was not significant (P <0.05). In conclusion, supplementation of broiler diets with enzyme and probiotic in wheat-soybean meal-based diets can improve the carcass yeild and relative length of the small intestine.