An experiment involving ,1* straight run one-day-old Hubbard broiler chicks was conducted on floor pens to investigate the e#ect of di#erent 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., ,2** and -*** kcal/ kg each with three levels of crude protein (CP) i.e., ,*, ,+ and "ῌ were o#ered to birds from hatching to ,2 d of age. Similarly, six broiler finisher diets with two

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... s of ME i.e. -*** and -,** kcal/kg andlevels of CP i.e. +0, +1 and +2ῌ, and +2, +3 and ,*ῌ, respectively, were o#ered during ,3῎., d of age. The chicks were randomly divided into +2 replicate of +/ chicks each and there werereplicates under each diet. Feed intake was significantly (pῌ*.*/) high in diet having low ME during both phase, with ,* and "ῌ CP during starter phase whereas all CP levels showed non-significant e#ects on feed intake at finisher phase. Low ME and high CP diets showed high feed intake (pῌ*.*/) during starter and finisher phases. Higher weight gains (pῌ*.*/) were observed at low ME diets during the experiment. Dietary CP contents at low ME did not a#ect 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 di#erences 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.