【摘要】 选用5头平均体重为27.86 kg健康三元(杜×长×大)杂交阉公猪,采用5×5拉丁方设计,以真可消化磷(True digestiblephosphorus,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-1 DMI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+1.140 9,r2=0.957 4。x表示日粮磷的摄入量,g.kg-1,DMI(DryMatter 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=0.679 4),而氮的总排泄量平均为12.14 g.d-1,各组之间没有显著差异(P=0.259 6),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影响氮的消化吸收利用。更多还原

【Abstract】 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,r2=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.更多还原