日粮磷水平对泌乳奶牛生产性能及磷表观消化率的影响

Effects of Dietary Phosphorus Levels on Milk Performance and Apparent Digestibility of Phosphorus in Dairy Cows

选用体况良好、产奶量、泌乳天数接近的泌乳奶牛分别饲喂含磷量不同(干物质基础)的日粮,研究日粮磷水平对泌乳奶牛生产性能及磷表观消化率的影响。试验结束前3d进行消化试验,收集试验奶牛的剩料及粪样并分析其干物质以及磷的含量。结果表明,(1)日粮磷水平对泌乳奶牛的产奶量、乳脂率、乳蛋白没有显著影响(P>0.05),当日粮磷水平高于0.50%时,泌乳奶牛的干物质采食量降低,随着奶牛日粮中磷水平的增加,奶牛的磷表观消化率逐渐降低;(2)日粮磷水平对奶牛粪中干物质排泄量影响不显著,但对粪中磷的排放量有显著影响(P<0.01)。随着日粮磷水平的增加,奶牛粪便中磷排泄量逐渐增加。

In order to study the effects of dietary phosphorus levels on milk performance and apparent digestibility of phosphorus in dairy cows, healthy milk were selected and fed concentrations with four levels P, feed and feces samples were collected during the last 3 days of trail period,the samples were tested for contents of dry matter and phosphorus.The results showed as follows： （l）The milk performance,milk fat,milk protein of dairy cows were no significantly affected by phosphorus levels of diets （P〉0.O5）,the dry matter intake decreased when phosphorus levels was greater than 0.5% ,the phosphorus apparent digestibility decreased when phosphorus levels increased. （2）The dry matter intake of feces was no significantly affected by phosphorus levels of diets,but the phosphorus of feces was significantly affected by phosphorus levels of diets （P〈0.01）.The phosphorus of feces increased when phosphorus of diets increased.