P and Ca requirements for Japanese quail
Nutrition is one of the most important factors in maintaining the physical condition of quails to achieve normal growth and optimize the production of eggs. As the feeding represents 60–70% of the farming investment, it becomes necessary to provide balanced feed with suitable proportions of nutrients to achieve success (Moraes and Ariki, 2002).
Determining the correct nutritional requirements is of great importance to all avian species, as the diet is perhaps the main environmental factor that determines whether the poultry will grow to its maximum genetic potential. Among the nutrients studied to establish the nutritional levels to be adopted, little attention is given to minerals, especially phosphorus, which is essential in poultry life during the growth phase, production for participating in the formation of the skeleton and contribution to the quality of the eggs. Furthermore, phosphorus is indicated as the third most expensive nutrient in a non‐ruminant feed, after energy and protein, particularly the sulphur amino acids and lysine (Bolling et al., 2000).
Although there are some national reports on the mineral requirement for Japanese quails at egg production phase (Murakami and Ariki, 1998), there is little or nothing regarding the phosphorus requirement for the growth phase determined by the factorial method to meet the animals' needs considering age, race, class or physiological situation and production system adopted (Gomes et al., 2004). Based on these, we aimed at estimating the nutritional requirement of calcium and phosphorus for Japanese quails reared under different temperature conditions using factorial design.