RESUMO
Three experiments were carried out to determine the crude protein requirements for maintenance (CPm) and weight gain (CPg) of meat quail and to develop protein-requirement prediction models. Experiment 1 was conducted to determine CPm by the nitrogen-balance technique. The regression of nitrogen balance on nitrogen intake revealed a CPm requirement of 2.94 g/kg0.75 /day. Experiment 2 was aimed at determining CPm by the comparative-slaughter technique. Retained nitrogen (RN) and nitrogen intake (NI) were quantified considering the metabolic weight of the birds. The linear regression of RN on NI provided a CPm estimate of 6.63 g/kg0.75 /day. Experiment 3 was conducted to determine CPg. The regression of body nitrogen from the carcasses on fasted body weight revealed CPg estimates of 407.68 (0-7 days), 501.76 (8-14 days), 470.40 (0-14 days), 517.44 (15-21 days), 627.20 (22-28 days), 423.36 (29-35 days), and 517.44 mg/g (15-35 days). The protein-requirement prediction models developed for meat quail aged 0-7, 8-14, 0-14, 15-21, 22-28, 29-35, and 15-35 days were CP = 2.94.W0.75 + 0.408.G; CP = 2.94.W0.75 + 0.502.G; CP = 2.94.W0.75 + 0.470.G; CP = 2.94.W0.75 + 0,517.G; CP = 2.94.W0.75 + 0.627.G; CP = 2.94.W0.75 + 0.423.G; CP = 2.94.W0.75 + 0.517.G, respectively, where: W0.75 = metabolic weight (kg), and G = daily weight gain (g).
