Alpha diversity analysis illustrating evenness, richness and diversity measures of cecal microbiome of chickens on d 35 of receiving a diet containing 0.15% bacitracin methylene disalicylate (BMD) at (150 g/ton) during the gowning phase: starter (d 1 to 10 of age), grower (d 11 to 24 of age), and finisher (d 25 to 35 of age), or a diet containing 0.05% salinomycin (SA) at (50 g/ton) during the gowning phase from d 1 to 35 of age, or a diet containing 0.05% salinomycin from d 1 to 35 of age and had access to medicated water containing 20 grams of penicillin G potassium (Pot-Pen)/100 liter of drinking water (SA + PP) from d 19 to 24 of age, or did not receive any medicated feed or water throughout the entire experiment (a negative control group). ∗ indicates a significant difference at the 0.05 level between CON, SA, SAPP, and BMC that were compared. n.s. indicate a no significant difference at less than 0.05 between CON, SA, SAPP, and BMD that were compared.