Comparing the effects of growth antibiotic promoter, some Iranian probiotics and similar imported products on performance, economic indicators and small intestinal morphology of broilers

This exprement was conducted to compare the effects of antibiotic and some Iranian and similar importedprobiotics on performance, economic indicators and intestine morphology of broilers. 540 1-day old broilers were used in a completly randomized design with 6 treatments and 5 riplicates per treatment. Pedi-Guard and Lacto-Feed were used as Iranian and Bactocell and Primalac probiotics as imported products. Treatments were: 1) basal diet (control) and basal diet with: 2) antibiotic, 3) Bactocell probiotic, 4) Pedi-Guard probiotic, 5) Primalac probiotic and 6) Lacto-Feed probiotic. Orthogonal contrasts were used to compare the effect of probiotics versus control and antibiotic, Iranian probiotics versus imported products and single strain probiotics versus multi strains. Primalac decreased feed intake and body weight gain, while antibiotic and Bactocell increased the feed intake and body weight gain in the starter period (P