Non-phytate phosphorus requirement for broilers from 8 to 21 days of age under heat stress conditions

作者：Cardoso Evandro Ferreira^*; Donzele Juarez Lopes; Miranda de Oliveira Donzele Rita Flavia; Sufiate Bruna Leite; Silva Amanda Dione; Tizziani Tarciso

来源：Tropical Animal Health and Production, 2018, 50(2): 317-325.

DOI：10.1007/s11250-017-1434-1

• Bone mineralization
• Ca to nPP ratio
• Heat stress
• Mineral excretion
• Thermal environment

Two trials were conducted to determine the non-phytate phosphorus (nPP) requirement for broiler under heat stress. In both trials, birds were distributed in a completely randomized 4 x 2 factorial design with four nPP concentrations: 0.25, 0.35, 0.45, and 0.55%, and two Ca supply techniques: Ca fixed at 0.899% (CaF) or varying along with nPP aiming a 2:1 Ca to nPP ratio (CaV). Both trials had eight pens/treatment, with nine and five birds/pen for exp. 1 and exp. 2, respectively. nPP concentration had no effect on feed intake (FI), body weight gain (BWG), feed conversion ratio (FCR), nor fat deposition ratio (FDR). nPP levels showed a linear effect on protein deposition ratio (PDR) only for CaF diets. The nPP levels had a significant effect, regardless the technique adopted, on tibia phosphorus (TibP), which varied quadratically, on tibia calcium (TibCa) that increased quadratically and linearly, respectively, on CaF and CaV diets, and on tibia ash (TibAsh) that showed a quadratic effect for both. No effect was observed on Ca to P ratio in the tibia (TibCa:TibP). The nPP levels showed a linear increase effect over phosphorus intake (PI), phosphorus excreted (PE), and phosphorus retained (PR), and a linear decrease effect on phosphorus retention coefficient (PRC). Therefore, the nPP requirement for broilers from 8 to 21 days of age that provided better performance and bone variables were 0.250 and 0.484%, respectively, for CaF diets and 0.250 and 0.511%, respectively, for CaV diets.

• 出版日期2018-2