An experiment was carried out to estimate dietary crude protein and energy requirements of 128 females of Japanese quails from 15 to 32 days of age, by the factorial method. A completely randomized design with four treatments with four replicates of eight birds was used. The treatments were: T1 = basal diet (BD) with 24.1% CP and 2,900 kcal AMEn ad libitum, T2 = 80%, T3 = 60% and T4 = 40% of T1 (close to maintenance). In the beginning of the experimental phase, four groups of 15 quails were slaughtered by cervical displacement. Gain requirements were obtained from twelve groups of 15 quails, reared separately and fed ad libitum, therefore, four groups of fifteen birds were slaughtered at 22, 29 and 32 days of age. At the final of the experiment, all birds from pens were slaughtered to estimate the requirements of maintenance by the comparative slaughter methodology. The prediction models to estimate daily requirements of CP and AMEn for Japanese quails maintenance and gain from 15 to 32 days of age were, respectively: CP (g/bird/d) = 4.752.W.75 + 0.865.G and AMEn (kcal/bird/d) = 91.480.W.75 + 8.86.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; growth; nutrient accretion; crude protein
