Digestible Methionine + Cysteine-to-Lysine Ideal Ratio for Meat-Type Quails at Initial Phase

Abstract

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.