Phosphorus requirements of quail chicks for optimizing performance

Phosphorus is a critical nutrient for optimal growth and bone development in Japanese quail chicks. This study was conducted to estimate the dietary requirement for available phosphorus in Japanese quails between 7 and 14 days of age, applying a univariate dose-response model across graded dietary levels (0.15-0.35%). A total of 375 quail chicks were randomly assigned to five dietary treatments with 5 pen replicates and 15 birds each, and performance parameters including body weight gain (G), feed intake (FI), and feed conversion ratio (FCR; feed efficiency) measured. Statistical analysis using broken-line regression models revealed that growth performance and feed efficiency were significantly influenced by dietary AP. The optimal AP requirements estimated from G ranged from 0.288 to 0.316%, while those based on FCR ranged from 0.282 to 0.331%. Considering model fit criteria, the recommended dietary AP requirement for quail chicks between 7 and 14 days of age is approximately 0.28 to 0.33%. These findings provide evidence-based guidance for phosphorus supplementation in early-stage quail nutrition, supporting efficient growth while minimizing excess phosphorus excretion and potential environmental impacts.