摘要:This experiment was conducted to compare the effects of antibiotic, probiotic, prebiotic and mixture of probiotic and prebiotic as dietary growth promoter on serum biochemical parameters, energy and protein efficiency of broiler chickens. Three hundred day old Ross 308 broilers were equally distributed into 30 floor pens and reared for 42 days. A basal diet was formulated according to the recommendations of NRC for starter (1 to 21 days) and grower (22 to 42 days) periods and considered as control diet. Four tested diets were formulated by supplementing the basal control diet with antibiotic, Flavomycin; probiotic, Primalac; prebiotic, Biolex-MB and mixture of probiotic plus prebiotic (synbiotic). Six replicates were used for each treatment. Specific growth rate and growth efficiency were highest in birds under prebiotic and synbiotic treatments in starter and total rearing period, respectively. Broilers that were fed diet containing synbiotic had the highest energy efficiency ratio which was significant as compared to control group. Protein efficiency ratio followed the same trend and improved when synbiotic was used in the diet (p < 0.05). At 21 and 42 day of age, dietary supplementation with probiotic and synbiotic decreased (p < 0.05) serum cholesterol concentration, when compared with birds fed Flavomycin diet. The results suggested that the mixture of probiotic and prebiotic could be effective as antibiotic to improve the health and performance of broiler chickens.