ABSTRACT This study was conducted to determine the optimal standardized ileal digestible arginine to lysine (SID Arg:Lys) ratio for Japanese quails in the egg-laying phase. A total of two hundred forty-five 35-week-old Japanese quails (181 ± 1.30 g initial body weight) were randomly assigned to five treatment groups with seven replicates of seven quails. Graded levels of L-Arginine were added to a basal diet in order to produce five SID Arg:Lys ratios (101, 106, 111, 116 and 121%). Collected data were analyzed as one-way ANOVA and optimal ratio was estimated using polynomial regression model (linear and quadratic) based on performance traits. Statistical differences were considered for p<0.05. Graded SID Arg:Lys ratios did not affect performance traits assessed. Based on results, the SID Arg:Lys ratio of 101% is sufficient to warrant proper performance of Japanese quails in the egg-laying phase.

ABSTRACT This experiment was conducted to evaluate the effects of dietary nitrogen-corrected apparent metabolizable energy (AMEn) levels on meat-type quail performance and carcass traits from 1 to 14d of age. A total of 1120 not sexed meat-type quails were randomly distributed to seven treatments, with eight replicates with 20 quails each. A basal corn and soybean meal-based diet was formulated to meet or exceed quail nutritional requirements, except for ME. Graded levels of soybean oil were added to the basal diet in replacement, to sand, to obtain dietary treatments (2,600; 2,700; 2,800; 2,900; 3,000; 3,100 and 3,200 KcalAMEn/kg diet). Data were analyzed as one-way ANOVA and optimum AMEn levels were estimated using polynomial regression model. Increasing in dietary AMEn levels elicited a linear decrease (p<0.01) in feed intake and nutrient intake (AMEn, protein and lysine). Quail weight gain and final body weight exhibited a quadratic response (p<0.03) to increased AMEn levels, being both optimized at 2820 KcalAMEn/kg diet. Graded AMEn levels elicited a linear increase (p<0.01) in carcass dry matter and fat content, whereas moisture content was linearly decreased (p<0.01). The protein content of the carcasses was not influenced (p>0.05) by AMEn. Based on the results, the dietary AMEn level that warrants adequate performance and carcass traits of meat-type quails from 1 to 14d of age is 2,820 Kcal/kg diet.

ABSTRACT This study was conducted to determine the optimum standardized ileal digestible isoleucine to lysine (SID Ile:Lys) ratio for meat-type quails from 15 to 35 d of age. Three hundred fifty not-sexed meat-type quails (Coturnix coturnix coturnix) were randomly assigned into five treatments, with seven replicates of 10 quails each. An isoleucine-deficient corn-soybean meal-based diet was formulated and graded supplemented with L-isoleucine (99%) to obtain diets containing SID Ile:Lys ratios of 55,61, 67, 73, and 79%. Data were analyzed as one-way ANOVA and optimum SID Ile:Lys was estimated by polynomial (linear and quadratic) regression. Statistical differences were considered when p<0.05. Quail performance from 15 and 21 d and 15 and 28 d of age was not affected by the treatments. From 15 to 35 d of age, body weight gain and body weight exhibited a quadratic response to increasing dietary SID Ile:Lys ratios, and were optimized at 66 and 67% SID Ile:Lys, respectively. Feed conversion ratio was not influenced by SID Ile:Lys ratios in any of the phases assessed herein. Based on the results, the optimum SID Ile:Lys ratio for meat-type quails from 15 to 35 d of age is 67%.

ABSTRACT This study was conducted to estimate the dig. valine to lysine (Val:Lys) ideal ratio for meat-type quails from 15 to 35 d of age. A total of 385, 15-day-old not sexed quails, were randomly assigned to five treatments, each one seven times replicated with eleven quails per experimental unit. Experimental treatments consisted of five dig. Val:Lys ratios (0.65; 0.70; 0.75; 0.80 and 0.85). Ideal dig. Val:Lys ratio was estimated using polynomial regression and linear broken-line regression model. Significant effect was considered when p≤0.05. Feed conversion ratio was not affected by dig. Val:Lys ratios in any of the assessed phases. From 15 to 21 d of age Val:Lys ratios increased linearly feed intake, weight gain and body weight. From 15 to 28 d of age, weight gain and body weight were both optimized by the Val:Lys ratio of 0.77. A linear effect of dig. Val:Lys ratios was observed on weight gain and final body weight from 15 to 35 d of age. From 15 to 35 d of age, according to linear broken-line regression model, the dig. Val:Lys ideal ratios for optimum final body weight and weight gain were 0.77 and 0.76, respectively. Based on the results the estimated dig. Val:Lys ratio for optimum meat-type quail performance from 15 to 35 d of age is 0.77

ABSTRACT This trial was performed to determine the ideal ratio of digestible methionine + cysteine (Met/Lys) with digestible lysine for meat-type quails from 1 to 14 days of age. A total of six hundred thirty, one-day-old, not sexed meat type quails were randomly assigned to six groups of treatments, each one with seven replicates and fifteen quails per experimental unit. A basal diet, methionine + cysteine-deficient, was graded supplemented with DL-Methionine (0.108; 0.169; 0.230; 0.291; 0.352 and 0.413%) to obtain the treatments, represented by six digestible Met/Lys ratios (0.60; 0.65; 0.70; 0.75; 0.80 and 0.85). Data was analyzed using ANOVA and polynomial regression and broken-line models were used to estimate the digestible Met/Lys ideal ratio, considering adjust of data to both models. Statistical significance was considered when p≤0.05. Feed intake, weight gain and final body weight was linearly increased as dig. Met/Lys ratio increased. Feeding conversion was improved with increasing in dig. Met/Lys ratios. A quadratic response on feathering percentage was observed with increasing dig. Met/Lys ratios. Digestible Met/Lys ratio which, maximized feathering percentage in meat-type quails, was 0.74. According to linear broken-line model, dig. Met/Lys ratio estimated for optimum feed intake, weight gain, final body weight and feeding conversion were, respectively, 0.66; 0.71; 0.71 and 0.74. The dig. Met/Lys ideal ratio for meat-type quails from one to 14 days of age is 0.74.

ABSTRACT Calcium (Ca) and available phosphorus (avP) requirements for egg production are different between the beginning and the end of the egg-production cycle. The objective of this study was to estimate the Ca and avP requirements of Japanese quails at end of the production phase. In total, 256 Japanese quails with 48 weeks of age were randomly distributed in 2 x 2 factorial arrangement consisting of two Ca levels (29 and 38 g/kg) and two avP levels (1.5 and 3.0 g/kg), totaling four treatments with eight replicates of eight hens each. The variables evaluated were feed intake (FI); egg production (EP); marketable egg production (MEP); egg weight (EW); egg mass (EM); feed conversion ratio per egg mass (FCRM); feed conversion ratio per dozen eggs (FCRD); livability (L); yolk weight (YW), albumen weight (AW), eggshell weight (SW); yolk percentage (YP), albumen percentage (AP), eggshell percentage (SP), specific egg weight (SEW); bone calcium percentage (BCa), bone phosphorus percentage (BP), bone ash weight (Bash) and bone ash percentage (PBash). There was no interaction between Ca and avP levels for any of the evaluated parameters, except for SEW. Quail performance was not influenced by the treatments, except for MEP. Bone characteristics were not influenced by the tested dietary Ca and avP levels. However, SW and SP increased and AP decreased as dietary Ca level increased. The dietary supplementation of 38 g Ca/kg and 3.0 g avP/kg may increase marketable egg production and the egg quality of Japanese quails at end of the production cycle.