Bovine Viral Diarrhoea

Bovine Viral Diarrhoea (BVD) is a viral infection that interferes with reproduction, reduces calf immunity leading to increased problems with pneumonia/diarrhoea and can cause mucosal disease. Infection in the pregnant animal can result in abortions, birth of stunted calves or those infected in the first four months that results in a live calf are ‘persistently infected’.

A persistently infected (PI) calf is unable to eliminate the virus as its immune system doesn’t recognise the virus as foreign. Therefore, PIs can spread the virus resulting in more infected animals but can appear like normal animals or have stunted growth. It is the detection and removal of PI calves from the herd that is critical to control and therefore eradicate BVD in cattle.

How is it spread?

• Across the placenta cow to calf

• Direct contact: saliva, nasal discharge, faeces, urine and semen

• Contaminated equipment: between animals and farms when sharing equipment

Testing options

• Milk antibody

• Blood antibody

• Blood antigen

• Ear Notch antigen

Antibody detects whether an animal has been exposed: been infected/ animal recovering/recovered / vaccinated

Antigen detects virus presence within tissue: current infection or PI animal

How to become BVD free?

• Blood test or ear tag test

• Vaccinate

• Biosecurity to prevent PIs getting on your farm

Testing is becoming mandatory in 2027