Effect of Bovine Leukemia Virus Infection on the Productivity of Dairy Cows

Abstract

We investigated the effect of infection with the Bovine Leukemia Virus (BLV) on productivity and reproduction in dairy cattle. The cattle from one dairy farm were assessed from May to December 2015 in this study. Productivity and reproduction data, which were obtained from the Dairy Herd Performance Test, were compared between the BLV-infected and uninfected cows. Milk yield and milk quality did not differ between BLV-infected (n＝160) and uninfected (n＝176) cows (P＞0.05). The open period did not differ between BLV-infected (n＝14) and uninfected (n＝18) cows (P＞0.05). There were no differences between the BLV-infected and uninfected cows. Enzootic Bovine Leukosis (EBL) occurred on the farm during the period of the survey. It is important to reduce the rate of BLV-infected cows to prevent EBL on a dairy farm.