Cardoso Evandro Ferreira, Donzele Juarez Lopes, de Oliveira Donzele Rita Flávia Miranda, Sufiate Bruna Leite, Silva Amanda Dione, Tizziani Tarciso
Department of Animal Science, Universidade Federal de Viçosa, Av. Peter Henry Rolfs, s/n, Campus Universitário, Viçosa, Minas Gerais, 36570-000, Brazil.
Department of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Av. Peter Henry Rolfs, s/n, Campus Universitário, Viçosa, Minas Gerais, 36570-000, Brazil.
Trop Anim Health Prod. 2018 Feb;50(2):317-325. doi: 10.1007/s11250-017-1434-1. Epub 2017 Oct 3.
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 × 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.
进行了两项试验以确定热应激条件下肉鸡对非植酸磷（nPP）的需求量。在两项试验中，鸡只均采用完全随机的4×2析因设计进行分组，设有四个nPP浓度：0.25%、0.35%、0.45%和0.55%，以及两种钙供应技术：钙固定在0.899%（CaF）或随nPP变化以达到钙与nPP 2:1的比例（CaV）。两项试验中每个处理均有8个栏舍，试验1和试验2中每个栏舍分别饲养9只和5只鸡。nPP浓度对采食量（FI）、体重增加（BWG）、饲料转化率（FCR）和脂肪沉积率（FDR）均无影响。仅对于CaF日粮，nPP水平对蛋白质沉积率（PDR）呈线性影响。无论采用何种技术，nPP水平对胫骨灰分磷（TibP）均有显著影响，其呈二次曲线变化；对胫骨灰分钙（TibCa）有显著影响，在CaF和CaV日粮中分别呈二次曲线和线性增加；对胫骨灰分（TibAsh）也有显著影响，两者均呈二次曲线变化。未观察到对胫骨灰分中钙磷比（TibCa:TibP）有影响。nPP水平对磷摄入量（PI）、磷排泄量（PE）和磷保留量（PR）呈线性增加影响，并对磷保留系数（PRC）呈线性降低影响。因此，对于8至21日龄的肉鸡，为获得更好的生产性能和骨骼指标，CaF日粮的nPP需求量分别为0.250%和0.484%，CaV日粮的nPP需求量分别为0.250%和0.511%。
