Supplementation of Streptococci strains isolated from different sources in commercial broilers

A total of 150, four-day old broiler chicks of Vancobb strain were randomly distributed into 5 groups. Each group had 30 birds with 3 replicates of 10 birds per replicate. The control group (T₁) was offered feed with culture medium only, whereas the treatments T², T₃, T₄ and T₅ chicks received Strptococcus lactis (S₁) from CFTRI Mysore, Streptococcus species (along with culture medium) isolated from molasses, turnip and kinnu juice, respectively, @ 6.8 × 10⁸ cells per kg fed. They were offered starter and finisher mash feeds upto 4 and 6 weeks of age, respectively. The feeds were formulated as per BIS specifications. All the chicks receiving probiotics showed significantly higher gain in weight, feed efficiency ratio and dressing percentage at the end of 6th week. The best feed efficiency ratio was recorded in T₂ treatment despite significantly lower feed consumption. There was a change in total count and Gram positive to Gram negative ratio in small intestine from 57: 43 to, 70 to 75: 30 to 25 in probiotic supplemented chicks. It was concluded that the isolatedstreptococci from the three sources were equally effective to their standard counterpart in improving the performance of broilers.