Energy requirements for maintenance and net efficiency of metabolizable energy utilization for maintenance and weight gain of Moxotó kids

Twenty-six Moxotó non-castrated male kids (averaging 15 kg of initial live weight (LW) and 6-8 months old) fed a diet with 2.6 Mcal of metabolizable energy were used to predict the net energy requirements for maintenance and net efficiency of metabolizable energy utilization (EMEU) for maintenance (km) and weight gain (kf). At the beginning of the experiment, six animals were slaughtered as reference to estimate initial body composition and initial empty body weight (EBW). Afterwards, five groups of four animals (one for each intake levels) were assigned to a complete randomized design, in the following treatments: 100% or ad libitum (AL), 85, 70 and 55 of ad libitum. Each group was slaughtered when BW of AL animals reached 25 kg LW. The net energy requirements for maintenance were estimated by the logarithm or exponential relations of heat production (HP) and metabolizable energy intake. Estimates of km and kf were calculated as the relation between dietary net energy for gain and maintenance, respectively, and the dietary ME concentration. After, ME and TDN requirements were estimated. The net energy requirement for maintenance of 55.11 kcal per kg EBW0.75 was next to the predicted by the North American report for this specie. This value is considered low if compared to that reported in the Brazilian literature. Km estimate was of 0.57. Kf estimates were of 0.22, 0.19, 0.28 and 0.36, respectively, for the concentrations of 2.99, 2.95, 2.56 e 2.5 Mcal/kg of DM.

growth; basal metabolism; empty body weight; requirement


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