Efeitos da fonte de energia e temperatura ambiente nas exigências de mantença e ganho de peso de codornas europeias: proteína, energia metabolizável, cálcio e fósforo

Abstract

The objective of this study was to evaluate the effect of replacing the feed energy source and the ambient temperature on the maintenance and gain requirements of European quails in protein, metabolizable energy, calcium and phosphorus. To estimate maintenance requirements, 432 10-day-old European quails were distributed in a completely randomized design, which were housed in two temperature-controlled rooms (26 °C and 35 °C), fed with three diets containing 15% metabolizable energy from the following sources: corn starch (AMI), isolated soy protein (PIS) and soy oil (OS) in three levels of feed supply (100, 70, 40% of ad libitum consumption), with four repetitions of six birds. The methodology used to determine maintenance requirements was that of comparative slaughter. At the end of the experimental period, at 30 days of age, all birds were slaughtered. The maintenance requirements were estimated by the retentions as a function of the consumption of protein, energy, calcium and phosphorus and the maintenance was considered as the consumption of each nutrient sufficient to avoid losses or gain in protein, energy, calcium and phosphorus, later converted to metabolic weight. A group of 40 quails were slaughtered at the beginning of the experimental period, at 10 days of age and the results were used to estimate the requirements for maintenance and gain. The gain requirements were estimated with 160 European quails and 40 birds were slaughtered at 15, 20, 25 and 30 days of age. These birds were housed in 4 groups of 40 birds in a room with thermoneutral temperature (26 °C). The gain requirements were estimated by the regression coefficient of the content of protein, energy, calcium and body phosphorus as a function of the weight of the empty body, divided by the efficiency of use. The nutritional requirements of growing European quails were influenced by the replacement of 15% of the energy in the AMI diet by the energy of PIS and OS and by room temperature. Considering the estimates of protein, energy, calcium and phosphorus requirements for maintenance and gain, prediction equations were elaborated following the models: PB (g/bird/day) = PBm * P0,75 + PBg * GP; ME (kcal/bird/day) = MEm * P0,75 + EMg * GP; Ca (mg/bird/day) = Cam * P0,75 + Cag * GP and P (mg/bird/day) = Pm * P0,75 + Pg * GP.