This experiment was carried out to estimate the crude protein and metabolizable energy requirements for maintenance and gain of 384 females of Japanese quails from 1 to 12 days of age. A completely randomized design with four treatments, with six replicates of ten birds each, was used. The treatments were: T1 = basal diet (BD) with 28% CP and 2,900 kcal AMEn ad libitum; T2 = 80%; T3 = 60% and T4 = 40% of ad libitum (close to maintenance). In the beginning of the experimental phase, four groups of 15 quails was slaughtered by cervical displacement. Gain requirements were obtained from 12 groups of 15 quails, that were separately reared and fed ad libitum. Therefore, four groups of fifteen birds were slaughtered at 4, 8 and 12 days of age. In the final of the experiment, all birds from pens were slaughtered to estimate maintenance requirements by the comparative slaughter methodology. The prediction equations to estimate daily CP and AMEn requirements of maintenance and gain of Japanese quails from 1 to 12 days of age were: CP (g/d) = 2.845.W.75 + 0.461.G and AMEn (kcal/d) = 77.07.P0.75 + 4.64.G, where CP is crude protein, W is live weight (kg), G is weight gain and AMEn is apparent metabolizable energy nitrogen-corrected (kcal).
energy; modeling; nutrient accretion; crude protein
