This work was carried out to compile data of two experiments (I and II) of energy and protein requirements, to enlarge the available information on nutritional requirements of bovine in national level. In the experiment I, 30 Nellore bulls were used and in the experiment II, 29 F1 Simental x Nellore bulls were used. In the both experiments, the animals were fed diets with 25, 37.5, 50, 62.5, and 75% of concentrate. The methodologies and the procedures were standardized and facilitated the overall analysis of the data. Regression equations of fat, protein and energy contents were fitted on the empty body weight (EBW) of animals. By deriving these equations, the composition of EBW gain was obtained. The results showed that, for live weight gain: empty body weight gain ratio, the live weight gain should be multiplied by the factor .964. The protein and energy net requirements of a 400 kg LW bovine were 140.26 g/kg empty body weight gain (EBWG) and 3.19 Mcal/kg EBWG, respectively. The MPm, MPg and CP requirements were 339.88 and 285.08 g/kg GPCVZ e 939,54 g/day, respectively. The ME and TDN requirements, for weight gain, were 8.62 Mcal/kg EBWG and 2.38 kg/kg EBWG, respectively, for diets with ME content of 2.4 Mcal/kg DM. For diets with ME content of 2.6 Mcal/kg DM, the requirements were of 6.38 Mcal/kg EBWG and 1.76 kg/kg EBWG, respectively.
energy; requirements; F1 Simental x Nellore; Nellore; protein
