Killing badgers is not a viable way to control bovine tuberculosis in cattle, researchers in Ireland have concluded.

In the first major paper on the country's Four Areas badger culling trial, published in Preventive Veterinary Medicine, the researchers stated: "Although feasible, we acknowledge that widespread badger removal is not a viable strategy for the long-term control of tuberculosis."

Dr Elaine King, chief executive for the National Federation of Badger Groups, said: "This trial suggests that badger culling only reduces TB in cattle if every single badger is exterminated."

The trial involved exterminating 2,360 badgers across 1,214 sq km in Cork, Donegal, Kilkenny and Monaghan between 1997 and 2002. This is similar to the proactive badger culling strategy currently being implemented in the Krebs' experiment in Britain, but badgers have been virtually eradicated from the study areas in Ireland.

TB in cattle from these removal areas was compared to TB in cattle from reference areas. The researchers report that the chance of a herd not having a TB outbreak for the next five years was between 7pc (Donegal) and 24pc (Kilkenny) higher in removal areas.

Dr King said: "We have been advised that the Republic of Ireland has slaughtered more than half its badgers over the last 10 years, reducing the population to less than 100,000 badgers. Badger densities are significantly lower in Ireland compared to Britain.

"Yet in 2002, the last year for which data are available, 6.5pc of Irish cattle herds were under TB restriction. In Britain, which has three times more badgers than Ireland, 3.6 per cent of herds are under movement restriction.

"Ireland's futile badger slaughter has simply confirmed that badger culling will never be a solution to the problem of bovine TB."

NFU vice president, Meurig Raymond, said: "As a matter of priority Defra must now find workable solutions to contain and eradicate this disease, and stop the emergence of new TB `hotspots'. The findings of the Irish study are a welcome addition to our understanding of this difficult and delicate problem and the Government would be wrong to ignore them as it seeks to develop a strategy to contain bovine TB."