Abstract

The effects of feeding baker’s yeast performance of Cobb 500 broilers were studied. Four nearly isocaloric and isonitrogenous starter and finisher rations were prepared. 240 chicks with an average initial body weight of 42g were randomly divided into 12 groups contained 4 treatments with 3 replications for each treatment. Treatment rations were containing 0, 0.5, 1.5 and 2.5% of baker’s yeast as T1, T2, T3 and T4 respectively. At the end of the trial, 3 males and 3 female chickens from each replication were slaughtered for carcass evaluation. The Crude Protein (CP) and Metabolizable Energy (ME) contents of baker’s yeast were 48% and 3615 kcal/kg DM, respectively. The CP content of the rations during the starter and finisher phases were 22% and 20%, respectively. The ME content of the rations during the starter and finisher phases were 3100 kcal/kg and 3200 kcal/kg respectively. Feed intake during the starter phase and entire trial period was lower for T4, whereas during the finisher phase in control diet group showed the highest feed intake than the other supplemental groups. The highest daily body weight gain was recorded in broilers fed T4 rations during starter phase, finisher phase and entire experimental period. Feed conversion ratio of T4 and T3 groups was better than T2 and T1. T3 and T4 groups had higher eviscerated percentages. Blood parameters results showed that fed broilers yeast containing ration had higher WBC, PCV and Hb. Partial budget analysis indicated that the highest net income, marginal rate of return and chicks’ sale to feed cost were obtained for T3 followed by T4. Baker’s yeast can be an important feed additive, which can be included up to 2.5% of the total ration and improve the overall performance of broilers without compromising the hematological indices of broiler chickens.