Calcium and phosphorus nutritional requirements of laying Japanese quails (<em>Coturnix coturnix japonica</em>)

Abstract

To determine calcium (Ca) and phosphorus (P) nutritional requirements, 512 laying Japanese quails were distributed in a completely randomized 4x4 factorial design (P levels available – 0.27%, 0.32%, 0.37%, 0.42%, and CA levels – 2.5%, 3.0%, 3.5%, 4.0%), with four replicates and eight quails per experimental unit. A linear interaction (p < 0.05) was observed between P and Ca levels for production percentage; the P level that maximized the interaction was 0.36% and the Ca level was 3.06%. Ca levels decreased linearly (p < 0.01) feed intake and eggs weight, but increased linearly the egg shell percentage (p < 0.01) and tibia strength (p < 0.05). P levels decreased linearly (p < 0.05) feed conversion (kg/dz) and caused a quadratic effect (p < 0.05) on feed intake, feed conversion (kg/kg), shell percentage and P percentage in bone; the optimum levels were, respectively, 0.36%, 0.36%, 0.37% and 0.35%. It may be concluded that the laying Japanese guail nutritional requirements are 2.5%Ca and 0.36% P.