This experiment was conducted to evaluate the effect of phytase addition on the use of feeding ingredients for laying quails. It was used 200 female Japanese quails at 251 days of age at an average weight of 187.2 ± 6.0 g and egg production rate of 84.8%. The quails were distributed in a complete random design with four experimental diets and five repetitions of ten birds per experimental unity. The experimental diets were consisted of corn and soybean meal based feedings formulated in order to meet the nutritional requirements of the quails and to the recomendations of phytase matrix supplemented with 0, 200, 400 or 600 phytase units (PU/kg). By using the method of total excreta collection, it was determined the values of ingested dry matter, excreted dry matter, apparent metabolizable energy (AME), apparent metabolizable energy corrected by nitrogen retention (AMEn), and the coefficients of energy metabolizability corrected or not by nitrogen balance. It was also calculated the quantities of phosphorus, calcium, and nitrogen retained by bird/day. In general, there was an improvement on the use of energy from feeding with phytase supplementation. Levels of 195 and 186 PU/kg resulted in a better use of AME and AMEn. There was no difference on retention of phosphorus and calcium. Level of 600 (PU/kg) promotes the lowest nitrogen excretion, however, 368 PU/kg is enough for a maximal retention of nitrogen by the quails.
enzyme; metabolism; nitrogen; phosphorus; quails nutrition
