ABSTRACT The objective of this study was to estimate the nutritional requirement of digestible methionine + cystine for Japanese quail during the growth phase and its residual effect on the laying phase. One experiment was conducted, including three phases: starter, from 1 to 14 days of age; grower, from 15 to 42 days of age; and laying, from 43 to 168 days of age. The experimental design was entirely randomized with five treatments (0.52, 0.64, 0.76, 0.88, and 1.00% of digestible methionine + cystine) and five replicates. In starter phase, 48 quail/experimental unit (box) were used; in grower phase, 31 quail/experimental unit (box) were used, which were reared until 14 days old, receiving conventional feed and, in laying phase, 12 quail/experimental unit were selected from grower phase to evaluate the residual effect. To evaluate animal performance, feed intake (g/bird), body weight (g), weight gain (g), feed conversion (g/g), and viability (%) were analyzed. At 14 and 42 days of age, the relative weight (%) of liver, spleen, and cloacal pouch organs, the birds’ warping (%) and body chemical composition (%) were evaluated. During laying, performance and egg quality were evaluated. In the starter and grower stages, quadratic effects were observed for all performance variables. Laying performance results confirmed the estimates obtained in the grower phase; however, there was no effect on egg quality. Considering the best feed conversion, the nutritional recommendation of digestible methionine + cystine for Japanese quail in the starter phase is 0.85% and in the grower phase, it is 0.77%, corresponding to daily intake of 50.43 and 158.5 mg of digestible methionine + cystine/day, respectively.

ABSTRACT The objective of this study was to evaluate the effect of the supplementation of two xylanases in the diet of meat-type quail on performance, morphology of the intestinal mucosa, metabolization of nutrients, and carcass yield. The experimental design was a completely randomized 2×3+1 factorial arrangement [two metabolisable energy reductions (70 and 140 kcal/kg), with or without the inclusion of two xylanases (A and B), plus a control treatment without xylanase), totalling seven treatments with five replicates and 42 quail each. Total excreta were collected at 28 days of age to determine the metabolisable coefficients of dry matter, crude protein (CP), neutral detergent fibre (NDF), and gross energy (GE). There was no interaction between the energetic reductions and inclusion of xylanases on performance variables of the birds. The 70 kcal/kg reduction led to better results for feed intake, weight gain, and feed conversion, while the 140 kcal/kg reduction led to worse results. In terms of jejunum morphometry, there was no interaction between energy reductions and inclusion of xylanases, although xylanases increased villi height and villus:crypt ratio. There was an interaction between energy reduction and inclusion of enzymes for the metabolisability coefficients of CP, NDF, and GE, leading to improvements in these coefficients. Xylanases A and B are effective in energy-reduced corn and soybean meal diets for 15 to 35-day-old quail.

RESUMO Objetivou-se avaliar a biometria das vísceras e os parâmetros sanguíneos de codornas de corte aos 14 e 35 dias de idade, suplementadas com diferentes níveis de selênio inorgânico e vitamina E. Utilizou-se um delineamento inteiramente casualizado, em esquema fatorial 4×4 (Se inorgânico = 0,1125; 0,2250; 0,3375 e 0,4500 mg/kg de ração x VE = 10; 23; 36 e 49 UI/kg de ração). No experimento de 0 a 14 dias, foram utilizadas 2.400 codornas recémnascidas, distribuídas em 16 tratamentos e três repetições de 50 aves cada. No experimento de 14 a 35 dias, sob os mesmos tratamentos, foram utilizadas 1.680 codornas com 14 dias de idade e três repetições de 35 aves cada. Aos 14 dias, o pesos relativo de baço (P=0,0203) aumentou linearmente em função dos níveis de VE, enquanto aos 35 dias, o peso relativo de bolsa cloacal (P=0,0390) aumentou linearmente em função do Se. Aos 14 dias, verificou-se interação (P=0,0097) vitamínica x mineral nas concentrações de colesterol total (CT), além de efeito quadrático (P=0,0138) relacionado aos níveis de Se e redução linear (P=0,0275) em função da VE. Aos 35 dias, as concentrações de CT (P=0,0055) e triglicerídeos (TGR, P=0,0220) apresentaram efeito quadrático para o Se. O aumento linear do peso do baço e bolsa cloacal aos 14 e 35 dias respectivamente, sugerem melhora na resposta imune em função da suplementação de VE e Se. Para a mínima concentração de CT e TGR aos 35 dias de idade, recomenda-se a suplementação de 0,26 e 0,29 mg/Se/kg/ração respectivamente.

SUMMARY This study aimed to evaluate biometric viscera and blood parameters of quails at 14 and 35 days of age, supplemented with different levels of inorganic selenium and vitamin E. A completely randomized design was used in a 4×4 factorial scheme (inorganic Se = 0.1125, 0.2250, 0.3375 and 0.4500 mg/kg diet x VE = 10, 23, 36 and 49 IU/kg feed). In the 0-14 days experiment, 2,400 newborn quail were used, distributed in 16 treatments and three replications of 50 birds each. In the 14-35 days experiment, 1,680 14 day-old quails were used with same treatments and three replicates of 35 birds each. At 14 days, the relative spleen weights (P=0.0203) increased linearly as a function of the VE level, while at 35 days, the relative weight of the bursa (P=0.0390) increased linearly as a function of Se concentration. At 14 days, there was a vitamin x mineral interaction (p=0.0097) affecting total cholesterol (TC), and a quadratic effect (P = 0.0138) related to Se and linear reduction levels (P=0.0275) as a function of VE. At 35 days, the TC concentrations (P=0.0055) and triglycerides (TG, P = 0.0220) showed a quadratic effect for Se. The linear increase in spleen weight and bursa after 14 and 35 days respectively suggests an improved immune response as a function of VE and Se supplementation. To achieve the lowest concentration of TC and TG at 35 days of age, supplementation of 0.26 and 0.29 mg/Se/kg/feed, respectively, is recommended.