The effect of feeding antibiotic and probiotic on the immune status and carcass characteristics of broilers*

An experiment was carried out in broilers from zero to seven weeks to evaluate the effect of feeding antibiotic and probiotic on the immune status against Ranikhet disease and carcass characteristics. Supplementation of both Virginiamycin (10 mg/kg) and Lactobacillus sporogenes (10,000 spores/kg) either separately or in combination in broiler diet had significant (P<0.01) reduction in intestine weight and had no effect on ready-to-cook yield, heart, liver and gizzard weights. Dietary supplementation of L.sporogenes had significantly improved the immune status against Ranikhet disease in broilers at 28 (P<0.01) and 49 (P<0.05) days of age post vaccination.