To evaluate the compressional effect of different levels of a multi-strain probiotic with antibiotic growth promoter, 300 Ross 308 day-old broiler chicks were employed in a completely randomized design manner with 5 treatments and 3 replicates with 20 chicks each. Dietary treatments were 1) control basal diet, 2) basal diet with 0/45% Flavomycin antibiotic growth promoter, 3) basal diet with 0.0365% Primalac® probiotic, 4) basal diet with 0.0475% commercial Primalac®probiotic and 5) basal diet with 0.0593% of Primalac® probiotic. Result showed significant favorable changes among dietary treatments on body weight, feed conversion ratio, liver, the stomach (fore stomach), liver, cholesterol, triglyceride, ALP, HDL, LDL, albumin, total protein, ND, IBD, AI, bacterial counts of E. coli bacteria, coliforms, and salmonella, villus height, crypt depth and villous height to crypt depth ratio of small intestine. In conclusion, dietary different levels of Primalac® could reveal a similar impact on studied parameters of broilers and all 3 levels of Primalac® might be good replacer to AGPs
