ABSTRACT
Use of synbiotic and zinc sources had synergetic effects on broiler chickens performance and immune response improvements. This experiment was carried out to evaluate the effect of synbiotic and zinc sources on broiler chickens performance, immune response and gut morphology. A total of 780, one-day old male broiler chicks were randomly assigned in factorial methods to 13 different experimental diets with 15 birds per replicate and 4 replicates per experimental diets for 7 weeks. The experimental diets contain unsupplemented basal diet and basal diets supplemented with varying concentrations of symbiotic [1-1.5g /kg of diets] and zinc oxide/Bioplex Zn [50- 150mg/kg of the diets]. In the unsupplemented basal diet weight gain was lower, feed intake and feed conversion ratio were greater than others [p<0.05]. Antibody titer only in birds, fed on diets supplemented with synbiotic and zinc oxide [1.5 g of synbiotic/kg of the diets and Bioplex Zn 150 mg/kg of the diets] increased significantly [p<0.05]. In duodenum the highest vili length was obtained in diet supplemented by 1.5 g synbiotic plus 150 mg /kg of diet and crypt depth in diets containing 1.5 g synbiotic/kg and 50-150 mg Bioplex Zn/ kg of diet significantly was lower than others [p<0.05].Villus in jejunum were affected of interaction effect of synbiotic and diet zinc level as in diet supplanted by 1.5 g synbiotic plus 150 mg Bioplex Zn /kg of diet were more than others and crypt depth only in diets supplemented whit 1.5 g synbiotic plus 50-150 mg Bioplex Zn was lower than basal diet [p<0.05]. Highest amount of villi high/crypt depth ratio was observed in diets supplemented by 1.5g synbiotic plus 100-150 mg zinc oxide and 50-150 mg Bioplex Zn/ kg of diet[p<0.05]. The best production efficiency factor was observed in diet containing 1g synbiotic plus 100 mg zinc oxide. Also supplementation of diet by 1.5 g synbiotic and 150 mg zinc oxide and Bioplex Zn had positive effects on immune response and gut morphological structure in broiler chickens