Bovine viral diarrhoea virus (BVDV) may not be a household name but it costs Irish farmers more than €100 million each year and a new programme devised by Animal Health Ireland (AHI) is set to eradicate it completely from the country by the end of the decade.

AHI is a not-for-profit organisation established as a private public partnership in 2009 with the mandate to provide leadership at national level for non-regulated diseases with the goals of enhancing the profitability and sustainability of individual livestock farms, enhancing the profitability of the food processing industry and enhancing the quality, image and competitiveness of Irish livestock and food in the marketplace.

The idea to develop a BVDV eradication programme came about shortly after AHI's foundation, according to communications manager Grainne Dwyer.

“One of our first jobs was to determine the priority issues for farmers and the industry. We couldn’t believe it when BVDV came out on top and that both farmers and industry wanted to see it controlled first.”

BVDV is an infectious agent of cattle and is recognised to be the cause of significant financial losses in cattle production in Ireland and elsewhere.

These losses arise through cows losing their calves either through embryonic death or abortion as well as through the birth of deformed animals and reduced milk production. Eradication of the disease has been identified as being very important in meeting the country’s targets for agriculture under the Food Harvest 2020 programme.

The disease is passed onto calves while in the womb. “Cows pick it up in the first three months of gestation,” Dwyer explains. “If they do the calf will be persistently infected and will be a source of infection for the rest of the herd.”

These persistently infected (PI) calves may look normal but they will spread the virus throughout their lives. The AHI programme is aimed at identifying PI calves as early as possible. The solution normally is to cull these calves and this will prevent the further spread of infection.

“Unless they are culled they can cause enormous problems for farmers,” she points out. “There was a case reported recently of a farmer who inadvertently kept a PI in his herd and out of 70 calves born 26 were PIs and had to be culled. This represented a huge cost to that farmer.”

The AHI programme involves a cost effective laboratory test of the sample of skin from the calf’s ear which is produced as a result of them being tagged. If a sample comes back positive the farmer waits three weeks and has the animal retested to make sure it is a PI and then takes appropriate action.

“If a calf has picked up the infection from a PI they are only transiently infected and will recover in a few weeks,” says Dwyer. “We carry out the second test to sort out the transiently infected from the persistently infected animals.”

The programme was piloted on a voluntary basis in 2012 and was proven to be successful. “We had to make sure that the labs could cope with the demand for tests before rolling out the compulsory programme in 2013,” Dwyer points out. “We have had a compliance rate of more than 99 per cent and we are already seeing a reduction in the number of PI calves born this year. The plan is to get rid of PIs over three years and have the disease eradicated by the end of the decade.”