Determination of Optimum Level of Threonine in the Diet Laying Japanese Quail of During 10-17 Weeks of Age

This experiment was conducted to determine in the threonine requirements laying japanese quail. A total of 240 female Japanese quails were used from 10 to 17 weeks of age, in a completely randomized design (CRD). Experimental treatments consisted of three treatments: basal diet (0.69% threonine), basal diet+0.05% L- threonine (0.74% threonine) and basal diet+0.1% L- threonine (0.79% threonine), with 4 replicates and 20 quails in each. Feed intake, egg production, egg mass, feed conversion ratio and body growth rate were recorded during this study. Egg quality traits were measured biweekly. Performance parameters were not affected by supplementation L- threonine. Quail requirement for threonize was evaluated using, linear regression and quadratic equation. The lowest feed intake and the highest thin albumen of height showed by 0.74% dietary threonine with a quadratic trend. Albumen height, albumen index, yolk color and Haugh unit were decreased linearly by increasing threonine levels. Based on these results, it is concluded that the 0.69% threonine level in the diet was enough to achieve the potential of egg performance in of laying Japanese Quail.