author(s)
Hitesh Singh, Manoj Kumar Bansala, Jagdeep Kumar, Somnath, Raj Kumar and Nazim Ali

abstract
One hundred twenty, one-day-old male broiler chicks (Cobb 400 strain), were randomly assigned to 4 treatments (30 birds/treatment). Treatment groups were; Control group in Standard ration, probiotic in Standard ration0.1% (treatment 2), probiotic in Standard ration 0.2% (treatment 3) and probiotic in Standard ration0.3% (treatment 4). Chicks were reared for 42 days. Body weight, feed consumption and feed conversion were weekly determined. Probiotic have been used in poultry industry for decades to promote growth and protect animals from diseases, followed by various side effects. In efforts of searching for a better alternative, probiotic is of extensive attention. The results of this study indicated that feed consumption for the entire period (up to 6 weeks) were significantly (P<0.05) increased in the treatments 1 and 4, when probiotic was added at a rate of 0 and 0.3%, compared with the other treatments (2 and 3). Body weight gain for the entire period (up to 6 weeks) were significantly (P<0.05) increased in the treatments 2, 3 and 4, when probiotic was added at a rate of 0.1, 0.2 and 0.3%, compared with the other treatments (1). These birds also had a significantly (P<0.05) higher feed conversion ratio than others and finally the lowest feed cost per kg of body weight was observed in the group containing probiotic.