Mathematical models to predict the energy requirements of Japanese quails from 01-35 days age

The objective of the work was to estimate maintenance and energy gain requirements in the phases: 01 to 15 and 15 to 35 days of age. For maintenance energy, 240 quails (per phase) were used according to a completely randomized design, with four treatments (ad libitum, 75%, 50% and 25%), six replicates, and ten quails per experimental unit (n = 655). Comparative slaughter group (35-initial phase; 25-growth phase). To estimate energy for gain, groups of 15 quails were slaughtered at 3, 6, 9, 12 and 15 days of age, in the initial phase, and groups of 10 quails at 20, 25, 30 and 35 days of age, in the growth phase. All slaughter was performed after a 12-hour fast. The equation of energy retained as a function of consumption made it possible to estimate an endogenous energy loss around 9.30 and 19.59 kcal/kg0.67/day and maintenance requirements at 54.96 and 91.48 kcal/kg0.67/day, respectively for the initial and growth phases. The angular coefficient of the line obtained by the linear relationship between energy retained and carcass weight over time allowed estimating the net weight gain requirements around 1.40 and 1.89 kcal/g, respectively, for the initial and growth. EMA 1–15d = (54.96 × P 0.67 ) + (8.30 × WG). EMA 15-35d = (92.11 × P 0.67 ) + (8.91 × WG). EMA - apparent metabolizable energy, (Kcal/quail /d); P, live weight (kg); WG, weight gain (g/quail/d).