Effects of 5% Biological Compound Premix on Milk Perform ance and Quality in Dairy Cow

This study was to investigate the effect of biological compound premix on the performance and milk quality in dairy cows. Twenty Holstein cows, with the similar age, parity, lactating month, gestation period, milk quantity and body weight, were randomly divided into two groups. The cows in two groups were fed with either common compound premix as control or 5% biological compound premix as treatment group. Two treatments contained same basal diet but different composi- tions of premix. The feeding experiment lasting 74 days displayed that daily milk quantity in treatment group was significantly higher than control group （P 〈 0.05 ）. The milk fat percentage was increased significantly in treatment group with the extended lactation time than control group （P 〈 0.05 ）. The milk protein and solids percentage were raised, but no significant difference was found between the two treatments （P 〉0.05 ）. The results indicated that 5% biological compound premix supplied in basal diet could facilitate to increase the milk performance and to ameliorate the milk quality of dairy cows.