The experiment aimed to estimate the crude protein (CP) and metabolizable energy (ME) requirements for maximum performance of male Japanese quails reared for meat production purpose and to further estimate the slaughter age for maximum weight of quails. Four hundred and fifty quails were used in a completely randomized design with five replicates of six quails per experimental unit. The treatments, consisting of the combination of five levels of CP (18, 20, 22, 24 and 26%) and three level of ME (2800, 3000 and 3200kcal/kg of diet), were allotted to the plots, while the four periods, to the split-plot. The studied traits during four periods (5 to 16; 16 to 27; 27 to 38 and 38 to 49 days of age) were feed intake (FI), weight gain (WG), feed:gain ratio (FG) and body weight (BW). During the whole period (5 to 49 days of age) the studied traits were total feed intake (TFI), total weight gain (TWG) and total feed:gain ratio (TFG). The estimates of CP and ME requirements, during the first (5 to 16) and third (27 to 38 days of age) periods were: 26 and 2800 and 18% and 3200kcal/kg of diet. The CP requirement in the second period (16 to 27 days of age) was 26%, however, it was not possible to estimate the ME requirement. In the fourth (38 to 49 days of age) experimental period, the estimated ME requirement was 3200kcal/kg of diet, however, it was not possible to estimate the CP requirement. For the whole period, the crude protein and metabolizable energy requirements, estimated for maximum total weight gain were 26% and 3200kcal/kg of diet, respectively. The estimated ages for maximum BW depended on the CP and ME level of diet, and varied from 57 to 85 and 60 to 74 days, respectively.
Japanese quails; crude protein; metabolizable energy; nutritional requirements
