中文摘要：

选用5头平均体重为27．86kg健康三元牡×长×大）杂交阉公猪，采用5×5拉丁方设计，以真可消化磷（True digestible plosphorus．TdP）为指标，配制了5种日粮真可消化磷含量不同的生长猪试验日粮，并使其总钙与TdP的比例为2：1，来研究日粮真可消化磷水平对氮、磷的消化率及其排泄量的影响。结果表明，在日粮真可消化磷含量低于0．26％时，日粮磷的真消化率随着日粮真可消化磷含量的上升而升高，当日粮真可消化磷含量超过0．26％后达到0．39％时，磷的真消化率陡然下降，由52．69％下降到49.56％。由试验结果可以推导出，当日粮真可消化磷含量在0．34％左右时日粮磷的真可消化率达到最高56．6％。但是各试验日粮之间磷的真消化率差异并不显著。当以g·kg^-1DMI为单位时，粪磷排泄量随着日粮磷摄入量的增加线性增加，线性方程为：y=0．493x＋1．1409，r^2=0．9574。x表示R粮磷的摄入量，g·k^-1，DMI （Dry Matter Intake）；Y表示粪磷排泄量，g·kg^-1，DMI。日粮5对应的粪磷排泄量极显著高于日粮1（P〈0．001）、日粮2（P〈0．001）、日粮3（P=0．001）和日粮4（P〈0．001），试验日粮1、2、3和4之间没有显著差异。当以g·kg^-1 feces DM为单位时，日粮5对应的粪磷排泄量最高（25．82），极显著高于日粮1（P〈0．001）、日粮3（P=0．005）和日粮4（P〈0．001），显著高于日粮2（P=0．021），日粮4对应的粪磷排泄量最低（21．28），除了显著低于日粮5以外，还显著低于日粮2（P=0．006）和日粮3（P=0．029）。日粮粗蛋白的平均表观消化率为81．6％．且各组之间受日粮真可消化磷含量的影响差异不显著（P=0．6794），而氮的总排泄量平均为12．14g·d^-1，各组之间没有显著差异（P=0．2596），氮的沉积率在66％，74％之间，各组之间差异也不显著，可见日粮真可消化磷水平并不

英文摘要：

5 Duroc × Landrace ×Yorkshire barrow were selected, with average initial body weight 27.86 kg. 5×5 Latin square design was used. Five experimental diets were designed with five true digestible phosphorus （TdP） levels, and the ratio of total calcium to TdP was 2：1. The results indicated that the true P digestibility increased with the increase of dietary TdP concentration when the dietary TdP concentration below 0.26%. When dietary TdP concentration increased from 0.26% to 0.39%, the true P digestibility dropped sharply, from 52.69% to 49.56%, The true P digestibility reached biggest value （56.6%） when dietary TdP concentration was 0.34%. But there was no significant difference among five diets. Based on DMI （Dry Matter Intake, g·kg^-1）, fecal P excretion increased linearly with the increase of P input, and linear equation was y=0.493x＋1. 140 9, r^2=0.957 4 （x was dietary P input （g· kg^-1 DMI）, y was fecal P output （g· kg^-1 DMI））. The true P digestibility value of dietary 5 was significantly higher than the values of dietary 1, dietary2, dietary 3 and dietary 4 （P〈0.01）, and there were no significant difference among dietary 1, dietary 2, dietary 3 and dietary 4. Based on feces DM （g· kg^-1）, fecal P output was highest in dietary 5, higher than dietary 1, dietary 2, dietary 3 and dietary 4（P〈0.05）. The fecal P output of dietary 4 was lowest, lower than dietary 2, dietary3 and dietary 5（P〈0.05）.The average apparent crude protein digestibility and the average nitrogen output were 81.6% and 12.14 g·d^-1 respectively, with no significant difference among the groups. The retention of nitrogen was 66% -74% and there was no significant difference among the groups, indicating that the dietary phosphorus levels could not influence the digesting and absorption of nitrogen.