Effect of Probiotic on Performance and Immunocompetence in Broiler Chicks

Abstract

An experiment was conducted with three hundred broiler chicks to evaluate the influence of dietary supplementation of probiotic Bacillus subtilis on performance and immunocompetence in broiler chicks. Body weight gain of birds fed diet supplemented with 50 mg/kg of probiotic were significantly higher during 1-21 and 22-42 days than birds fed the control diets. Feed conversion of birds fed diet supplemented with 50mg/kg of probiotic were significantly better from 22 to 42 days than birds fed the control diets. In each of the 7, 14, 21 and 28 days of age, twenty birds per dietary group were injected intravenously (brachial vein) with 0.1ml of 0.5% sheep red blood cell (SRBC). The probiotic had positive effect on production and persistency of antibody in response to SRBC antigen. Antibody production against Newcastle disease virus in 50mg/kg probiotic supplemented group was significantly higher at 10 days of post immunization compared to control. The results suggest that the use of probiotic containing Bacillus subtilis had positive effect on performance and immune system of broiler chicks.