Bovine Viral Diarrhoea (BVD) is a well-recognised cause of reproductive loss in cows, reduced growth rates and occasionally fatal disease in young stock. Research indicates that 90% of dairy herds have been exposed to infection with the virus. The main problem occurs when pregnant cattle with no immunity become infected. This can result in high numbers of empty cows at pregnancy testing. A new bulk milk test is now available for testing your herd for BVD virus. The new bulk milk test can determine the level of infection in a herd and the percent of the herd that is at risk. You can then decide whether or not it is worthwhile to protect cows from BVD by vaccination before pregnancy. The best time to test is prior to the start of mating once all the cows have calved. The sample is taken from your bulk milk by the dairy company. If you think this test may be applicable for you or you are interested to find out more please talk to your vet.