不同磷源对育成母牛日粮磷表观消化率的影响

Effect of Different Sources of Dietary Phosphorus on Phosphorus Apparent Digestion in Heifers of Holstein Cows

本文旨在采用消化试验研究育成母牛日粮中不同磷源（植物磷源或补充部分矿物磷源）对日粮总磷表观消化率的影响。试验选用体况良好、体重一致的15月龄荷斯坦育成母牛12头，随机分为3组，即试验1组、2组和3组，每组4头，分别定量（3．50kg／d）饲喂3种不同精料日粮，粗料（青贮）自由采食，以磷酸氢钙替代部分植物磷源，日粮总磷为0．57％-0．60％；试验期为30d，预试期20d后进入正试期，试验最后7d全收集粪样和尿样；结果表明不同磷源处理间日粮的总磷消化道表观消化量和表观消化率没有显著差异（P〉O．05），总磷的表观消化率为38．2％。

To evaluate dietary phosphorus apparent digestion, 12 Holstein heifers cows grouped by parity were assigned at feeding to diets supplemented with Wheat bran, barley and cottonseed meal. Test group 1 contain 0.60% phosphorus using organic sources, Test group 2 or 3 contain 0.57% P of using dicalcium phosphate as the supplemental source of phosphorus（the dicalcium phosphate was contain 0.8 or 2.3 percent in concentrate）. The diets were fed to 12 heifers （three treatment） for one months. All feces were collected using the direct collection feces during Last week. The results showed that apparent digestibility of dietary phosphorus did not differ due to source of supplemental phosphorus, averaging 38.2% across diets.