Effects of probiotics (bacillus subtilis and bacillus licheniformis) on the performance and antimicrobial activity of broiler chicken

Abstract

This study was conducted to investigate the efficacy of probiotics on the performance and antimicrobial activity of broiler. A total of 300 one-day old of Cobb-500 broiler chicks were divided into five experimental groups (T1-T5) in completely randomized design with six replicates as ten chicks in each replication. One of the five experimental groups fed diet without probiotic was as control (T1) and the remaining four groups fed diet with 4 levels of commercial probiotics were 20g BS/metric ton feed (T2), 50g BS/metric ton feed (T3), 20g BL/metric ton feed (T4) and 50g BL/metric ton feed (T5). Among the groups, T5 showed significantly (P˂0.05) higher body weight and lower feed intake than the others. Feed conversion ratio (FCR) was better in all probiotic treated groups compared to the control and the best FCR was found in T5 group. The weight of breast, wing and giblet was significantly (P<0.05) higher in T4 group and had no significant difference (P˃0.05) in thigh and drumstick as compared to others treatment groups and control (T1). Probiotics had significant difference (P˂0.05) on percentage of moisture and dry matter but no significance difference (P˃0.05) on water holding capacity (WHC) and ash percentage. Treatment groups found lower numbers of Escherichia coli and Salmonella but higher number of Lactobacilli rather than control group (P<0.05). Based on these results, it is concluded that dietary supplementation of probiotics improves the growth performance and intestinal microbial ecosystem of broiler chicken.