Influence of Diet Formulation Technique on Requirement of Digestible Lysine for Growing Japanese Quail: A Practical Reflection

This work aimed to investigate the influence of two diet formulation techniques: supplementation and dilution, on estimates of digestible lysine requirements in growing Japanese quail. For this, 492 Japanese quails (10 to 36 days old) with initial weight of 33.7 +/- 0.42 g were used, housed in overlapping cages, and distributed in a completely randomized design in a 2 x 5 factorial arrangement. Two formulation techniques (supplementation technique and dilution technique) and five levels of lysine (0.80; 0.90; 1.00; 1.10 and 1.20%) were used, thus composing 10 treatments and 6 repetitions with 8 birds each. Performance parameters, nutrient gain, and carcass components were evaluated. There was interaction (p <0.05) between the formulation techniques and the levels of digestible lysine tested for feed intake, weight gain, protein gain, fat gain, chilled carcass weight, breast weight and thigh percentage, in addition to the isolated effect of the formulation technique on feed conversion, and isolated effect of the levels of digestible lysine on feed conversion and thigh weight. The digestible lysine requirement values estimated for better performance and efficiency in nutrient deposition were 1.028% or 133 mg/day by the supplementation technique, and 1.063% or 140 mg/day by the dilution technique. It can be concluded that the requirement for digestible lysine in Japanese quail is influenced by the formulation technique, and the supplementation technique had better results.