Effect of Varying Levels of Energy and Protein on Live Performance and Carcass Characteristics of Broiler Chicks

Abstract

An experiment involving 270 straight run one-day-old Hubbard broiler chicks was conducted on floor pens to investigate the effect of different levels of energy and protein on live performance and carcass responses of broilers chicks. Six broiler starter diets with two levels of metabolizable energy (ME) i.e., 2800 and 3000kcal/kg each with three levels of crude protein (CP) i.e., 20, 21 and 22% were offered to birds from hatching to 28d of age. Similarly, six broiler finisher diets with two levels of ME i.e. 3000 and 3200kcal/kg and 3 levels of CP i.e. 16, 17 and 18%, and 18, 19 and 20%, respectively, were offered during 29-42d of age. The chicks were randomly divided into 18 replicate of 15 chicks each and there were 3 replicates under each diet. Feed intake was significantly (p<0.05) high in diet having low ME during both phase, with 20 and 22% CP during starter phase whereas all CP levels showed non-significant effects on feed intake at finisher phase. Low ME and high CP diets showed high feed intake (p<0.05) during starter and finisher phases. Higher weight gains (p<0.05) were observed at low ME diets during the experiment. Dietary CP contents at low ME did not affect the weight gain during starter phase whereas high CP with low ME showed high weight gain in finisher phase. The response of CP and ME was similar for good feed conversion ratio (FCR) as was observed for feed intake and weight gain. No significant differences of dietary treatments were observed on any of the carcass characteristics. From the recent study, it is obvious that low ME and high CP diets promised optimum performance for broiler chicks at both starter and finisher phases.