03 Jul 2016

What is BVD?

What is BVD?

Derek Armstrong, Vet with BVDFree England explains more about the disease.

Bovine Viral Diarrhoea or BVD is a highly contagious viral disease of cattle.  The majority of BVD infections occur after birth.

Signs of BVD aren't always obvious and the costs can be hidden:

  • Reproductive losses - early embryonic death, returns to service, abortions
  • Secondary disease – immune suppression increases the chances of pneumonia and scour in calves, lameness and mastitis in adults
  • Poor production - lower milk yield, poor growth rates, increased cull rates
  • Deaths - commonly through secondary
  • Infection

Persistently Infected animals (PIs)

If cows and heifers become infected within the first 120 days of gestation, the unborn calf may become persistently infected or PI. A calf will only become PI if its mother is infected during pregnancy; it cannot become PI after birth.

PIs will shed high quantities of BVD virus into their environment for life. They are the most significant source of infection to other cattle.

Within infected herds, PIs often only account for 1 or 2 out of every 100 animals. It is contact with these PI animals that leads to infection of other animals within your herd, causing the signs listed above.

How does BVD spread?

BVD virus is commonly spread

  • From infected dams to their unborn calf
  • Through the semen of infected bulls
  • From nose to nose contact with infected carriers.

Vaccinating can help control the disease - but will not eradicate the disease in infected stock - so you might be vaccinating and still have BVD on your farm.

Many UK herds have already been exposed to the virus, but there are many at constant risk of re-introduction of the disease due to:

  • Unknowingly buying in PI animals
  • Infection from neighbouring farms
  • Contact with infected animals at markets and shows

It is recommended that all results from health testing analysis are discussed with your veterinary surgeon before action is taken.

For more information on BVD CIS Tissue Analysis please contact Kate Cross katecross@thecis.co.uk or speak to your area manager.

BVD Factsheet

For more info on BVDFree England or to sign up to the voluntary scheme please visit the website www.bvdfree.org.uk