复合生物预混剂对奶牛生产性能和乳品质的影响

为探讨相同日粮条件下添加复合生物预混剂对奶牛生产性能和乳品质的影响，选取 20 头年龄、胎次、泌乳日龄、妊娠期、产奶量、体重基本相似且身体健康的荷斯坦奶牛随机分为2组，每组10头。分别饲喂对照组（普通型预混剂）和试验组（项目组研制的5%的复合生物预混剂）日粮，两种日粮基础配方相同，含预混剂不同，经74 d试验期显示：整个试验期对照组与试验组每头日平均产奶量差异显著（P<0.05）；随着泌乳期的延长，试验组乳脂肪率增加125%，显著高于对照组（P<0.05）；两组乳蛋白率和乳中总固形物含量有增加趋势，差异不显著（P＞0.05）。表明奶牛日粮中添加复合生物预混剂可以显著提高奶牛产奶性能、改善乳品质。

Effects of compound biologic premix on the performance of dairy cows and milk quality

The experiment was designed to study the effect of compound biologic premix on the performance and milk quality of dairy cows. Holstein cows were divided into two groups， each with 10 cows， with the similar age， parity， lactating month， gestation period， milk quality and body weight, and were randomly allocated to one of two treatment diets which included the same basal diet. Common compound premix was added in the control diet， and compound biologic premix was added in the test diet. In 74 d experimental period the results showed: the daily milk yield of treatment group was significantly higher than that of control group （P<0.05）. The milk fat percentage was raised by 125% in treatment group， and which was higher than that of control group （P<0.05）. The milk protein and solids percentage was increasing with the extended lactation time， but no significant difference was found between the two treatments （P >0.05）. We can conclude that 5% compound biologic premix supplied in basal diet was helpful to increase the performance of milk yield and to improve the milk quality of diary cows.