This study aimed to evaluate the effects of different stocking densities on the performance, eggshell quality, surface body temperature and hematological parameters of Japanese laying quails based on physiological indicators of animal welfare. Two hundred and thirty seven-week-old Japanese quails were used in this experiment. The quails were completely randomized to four stocking densities: 112.2 (T1), 102 (T2), 93.5 (T3), and 86.31 (T4) cm²/quail and five replicates each. Hematological parameters were analyzed as a 4x4 factorial design (stocking density X time) over four periods of blood sampling (25, 50, 75, and 100 days). To obtain the body surface temperature (Ts, °C) three thermograms (head, core and shin) were captured from each repetition per plot (2 repetitions per experimental plot) every 25 days (25, 50, 75, and 100 days). Feed intake, feed conversion per egg mass, feed conversion per dozen eggs, egg mass, egg production rate, and eggshell quality-related variables were not affected by treatments. However, egg weight (p = 0.023) and core temperature (p = 0.003) were influenced by different cage stocking densities. The heterophil/lymphocyte ratio increased (p = 0.01) with increasing time and stocking density. The mean corpuscular volume (p = 0.0001) as well as the total leukocyte count (p = 0.001) increased until the third blood sampling period (75 days) and then decreased in the last period. Different stocking densities do not interfere with the performance and eggshell quality of Japanese quails. However, the hematological parameters and head temperature are affected by different cage stocking densities and time.

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. EMA1–15d = (54.96 × P0.67) + (8.30 × WG). EMA15-35d = (92.11 × P0.67) + (8.91 × WG). EMA - apparent metabolizable energy, (Kcal/quail /d); P, live weight (kg); WG, weight gain (g/quail/d).

Six hundred and fifty five female Japanese quails were used to estimate the maintenance and protein gain requirements from one to 15 and 15 to 35 days of age. To estimate the protein for maintenance, 240 quails (per phase) were used according to a completely randomized design, with four levels of feed supply (ad libitum, 75%, 50% and 25%) and six replicates of ten birds. Comparative slaughter group (35 and 25 quails, respectively, in the first and in the second phase). To estimate the protein 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 phase growth. All slaughter was performed after a 12-hour fasting. The linear regression equation of the protein retained as a function of crude protein consumption made it possible to estimate an endogenous protein loss around 0.7 and 2.19 g/kg0.67/day and the maintenance requirements at 2.095 and 6.301 g/kg0.67/day, respectively for the initial and growth phases. The angular coefficient of the line obtained by the linear relationship between the retained protein and the carcass weight over time allowed to estimate the net gain efficiencies around 0.284 g/g (initial phase) and 0.310 g/g (growth phase). The equations for predicts daily protein requirements from one to 15 (PB1-15d) and from 15 to 35 days (PB15-35d) were respectively: PB1-15d = (2.095 × P0.67) + (0.851 × WG) and PB15-35d = (6.30 × P0.67) + (0.894 × WG), were P is live weight (kg) and WG is weight gain (g/quail/d).

Para a obtenção de maiores lucros na produção de codornas japonesas em postura é necessário a redução nos custos da formulação da dieta buscando a substituição de alimentos tradicionais por outros alternativos. Este trabalho tem por objetivo avaliar o os valores de energia metabolizável do sorgo baixo tanino para codornas japonesas em postura. Foram dois tratamentos e cinco repetições, sendo o tratamento 1 com a ração referência à base de milho e o tratamento 2 com 60% da ração referência e 40% do sorgo grão de baixo tanino. As codornas foram pesadas e distribuídas e receberam os tratamentos de acordo com o delineamento inteiramente casualizado. Foi usado o método de coleta total para determinação das energias metabolizáveis aparente (EMA) e aparente corrigida pelo balanço de nitrogênio (EMAn), com um período de adaptação de quatro dias e três dias de coleta de excretas e mensuração do consumo de ração.  Os valores de EMA e EMAn foram respectivamente 3.124 kcal/kg e EMAn 3.075 kcal/kg de ração.