生长猪植物性饲料可消化磷预测模型的研究

Study on Predicting Model of Digestible Phosphorus in Plant-origin Ingredients for Growing Pigs

本文旨在通过测定常用植物性饲料中总磷、植酸磷和天然植酸酶的含量,并结合动物试验的结果,探讨建立猪植物性饲料可消化磷预测模型的可行性,为磷资源的有效合理利用、降低养殖业排泄物对环境的磷污染提供简便方法。选用19种植物性饲料原料和2种配合饲料,在分析测定其总磷、植酸磷和天然植酸酶酶活的基础上,以25 kg左右三元杂交生长瘦肉型猪为试验动物,采用6×6(2个)、4×4(3个)拉丁方设计,以玉米淀粉-豆粕为基础日粮,分别按替代法和回归法,测得了单一饲料原料中磷的表观消化率和真消化率,并建立了可消化磷的预测模型。所建立的预测模型分别为:表观可消化磷(g/kg)Y=-0.411+0.405X1-0.227X2+0.003 15X3(R2=0.822,RSD=0.272,P<0.001),其中X1=总磷(g/kg),X2=植酸磷(g/kg),X3=植酸酶活(FTU/kg),下同;真可消化磷(g/kg)二元模型Y=0.062 9+0.655X1-0.412X2(R2=0.859,RSD=0.386,P<0.001),三元模型Y=-0.220+0.589X1-0.304X2+0.003X3(R2=0.882,RSD=0.244,P<0.001)。可以用饲料总磷、植酸磷和天然植酸酶酶活指标来预测植物性饲料可消化磷的含量,比较而言,对真可消化磷预测结果的准确性更高。

To study the feasibility of predicting the digestible phosphorus in plant-origin feedstuffs for pigs by the contents of total phosphorus （TP）, phytate phosphorus （PP） and intrinsic phytase activity （Phy）, five trials according to Latin Square design were conducted to evaluate P digestible values of 19 plant-origin ingredients and 2 compound diets for growing pigs with 25 kg initial body weight which based on analyzing the contents of their TP （X1· g/kg）, PP （X2· g/kg） and Phy （X3·FTU/kg） and their true digestible phosphorus were calculated by regression method. Some high-accuracy and applicable prediction equations were established in the present study as follows： Apparent digestible P （g/kg） = - 0.411 ＋ 0.405X1- 0.227X2 ＋ 0.003 15X3 R^2 = 0.822, RSD = 0.272, P〈 0.001; true digestible P （g/kg） = - 0.0629 ＋ 0.655 X1- 0.412X2 R^2= 0.859, RSD = 0.386, P〈0.001;truedigestible P （g/kg） = - 0.220 ＋ 0.589X1- 0.304X2＋ 0.003X3 R^2= 0.882, RSD = 0.244, P〈0.001. The digestible phosphorus in plant origin feedstuffs can be predicted by the linear equation of TP, PP and Phy. It is more accurate to predict the content of true digestible phosphorus than apparent digestible phosphorus with indices of TP, PP and Phy activity in plant feedstuffs.