Models for predicting protein requirements for meat quail

Abstract

Three experiments were carried out to determine the crude protein requirements for maintenance (CPm) and weight gain (CPg) of meat quail and to develop protein‐requirement prediction models. Experiment 1 was conducted to determine CPm by the nitrogen‐balance technique. The regression of nitrogen balance on nitrogen intake revealed a CPm requirement of 2.94 g/kg0.75/day. Experiment 2 was aimed at determining CPm by the comparative‐slaughter technique. Retained nitrogen (RN) and nitrogen intake (NI) were quantified considering the metabolic weight of the birds. The linear regression of RN on NI provided a CPm estimate of 6.63 g/kg0.75/day. Experiment 3 was conducted to determine CPg. The regression of body nitrogen from the carcasses on fasted body weight revealed CPg estimates of 407.68 (0–7 days), 501.76 (8–14 days), 470.40 (0–14 days), 517.44 (15–21 days), 627.20 (22–28 days), 423.36 (29–35 days), and 517.44 mg/g (15–35 days). The protein‐requirement prediction models developed for meat quail aged 0–7, 8–14, 0–14, 15–21, 22–28, 29–35, and 15–35 days were CP = 2.94.W0.75 + 0.408.G; CP = 2.94.W0.75 + 0.502.G; CP = 2.94.W0.75 + 0.470.G; CP = 2.94.W0.75 + 0,517.G; CP = 2.94.W0.75 + 0.627.G; CP = 2.94.W0.75 + 0.423.G; CP = 2.94.W0.75 + 0.517.G, respectively, where: W0.75 = metabolic weight (kg), and G = daily weight gain (g).

Protein and energy for maintenance and gain of European quail fed different energy sources and housed at two temperatures

“…The CP m requirements were close to those found by Nogueira et al (2019) In a study with heavy dams and with European quail, Rabello et al (2004) and Silva et al (2018), respectively, found an increase in CP m requirements when the birds moved from a cold to a warm environment. However, according to Oliveira et al (2006), the nutritional requirements of birds change with the temperature of the environment also as a result of the change in the size of the organs and that the larger the size, the greater the animal's requirement.…”

“…Estimates of CP g requirements were similar to the 0.55 g found by Jordão for European quail aged 16 to 36 days and reared in cages, and 0.52 g for European quail aged 15 to 35 days found by Nogueira et al (2019). Considering the utilization efficiency of the consumed protein for the net gain of protein in the empty body, higher CP g requirements were determined for the SO source at both temperatures due to the lower efficiencies when compared with the other sources.…”

“…The K ng of diets in the 26 °C room with CS, ISP, and SO sources were 33, 32, and 31%, respectively, constituting similar values found by Nogueira et al (2019) of 39.86% for meat quail from 15 to 36 days reared on the ground. In this study, we found 38, 43, and 36% at the temperature of 35 °C with the CS, ISP, and SO sources, respectively, constituting values close to 38% observed by Jordão Filho (2008) for meat quail from 16 to 36 days old raised in cages at 28 °C.…”