BVD causes severe infertility in a dairy Herd
Visited a dairy farm outside Derry where 220 dairy cows were presented for scanning. There was clinical evidence of 10% embryonic death among cows diagnosed pregnant. This was unacceptably high. This maybe partially explained by the fact that results of a milk test recently showed that there was at least one persistently infected (PI) cow for BVD in the herd. The resident veterinary practitician advised him to take a milk sample from all first lactation cows and pool same and similarly for second lactation cows. Having done this, the milk samples were to be tested for the presence of PI in the herd. In his opinion, the risk of a PI in third lactation cows and greater is minimal.