A study has found more than a quarter of Welsh beef and dairy herds are infected with Bovine Viral Diarrhoea (BVD).

The find comes from Gwaredu BVD, which is an industry-led programme funded by the Welsh Government Rural Development Programme (RDP) to eradicate BVD in Wales, giving Welsh livestock farmers access to up to £500 of funding to work with their vet to diagnose if their herd has been exposed to the virus, and to seek and remove any infected animals.

More than 3,000 herds have been tested in the first five months of the scheme and manager John Griffiths believes the findings show farmers must act.

"Of these, more than 25 per cent have tested positive," he said.

"That means as many as 750 of the herds tested to date are potentially underperforming as a result of infection. "While the total number of affected herds in Wales is unknown, it is clear that farmers must act now to stop the disease from spreading and to reduce its effects.

"BVD has the potential to cause significant financial losses as a result of poor fertility, reduced milk yields, low daily live weight gains, fever, diarrhoea and respiratory problems.

"On farm, this means more calves suffering from conditions such as pneumonia or scours and fewer calves being conceived.

"This can cost beef herds as much as £45 per cow per year and as much as £15,000 per year for an average 130-cow dairy herd."

Under the Gwaredu BVD scheme, all beef and dairy herds in Wales are entitled to free screening to test for the presence of the BVD virus: farmers can blood test up to five unvaccinated animals (ranging from nine to 18 months of age) from each management group within the herd for a maximum of three years. If these tests positively identify the BVD virus, an additional £500 is available for farmers to work with their vet to find any Persistently Infected (PI) animals.

The simplest, most cost-effective way of identifying PI animals is to use Tissue Sampling Tags (TSTs) as part of the normal tagging process for all newborn and recently purchased animals.

For more information about Bovine Viral Diarrhoea, or to access funding from the Gwaredu BVD scheme, farmers should speak to their farm vet.