Effects of Alfalfa Hay Supplementation on Milk Yield and Milk Fat of Dairy

16 having given birth dairy cattle(mid-lactation stage Holstein Cows) were selected according to similar age,body weight,birth order,physiological state and days in milk etc.were assigned randomly to 4 groups(control group A,test groups B,C,D),4 cows in each group,pre-test period was 10 d,test period was 30d.Mild production and milk fat were measured in this study.Based on the diet of control group,test diet of B,C,D added 3.5kg,6.5kg and 9.5kg alfalfa hay replace of part of fodder.The results demonstrated that compared with control group,milk production of test groups increased 4.18%,9.72% and 5.95%,respectively,there was significant difference(P0.05),there were significant difference among test groups(P0.05).Economic efficiency increased 6.41%,13.92% and 5.13%.