THE number of cattle herds with tuberculosis have been overstated for the past two years, Defra said this week.

Official figures dating back to 2011 showing new cases and the number of herds under restrictions following an outbreak of TB have been suspended, after a problem was identified with data recording.

The revelation was the latest issue to hit the Government’s policy to tackle TB in cattle, after efforts to cull badgers – which can spread the disease to herds – in two pilot areas failed to kill the target number and saw policing costs spiral to more than £2.4m.

On Wednesday officials said a number of herds which had been declared TB-free and had their restrictions lifted had still been recorded as not disease free.

Defra said figures for herds under restrictions in 2012 and 2013 were likely to be revised significantly downwards, after the Animal Health and Veterinary Laboratories Agency (AHVLA) had spotted the problem.

It could also affect figures for the incidence of new cases in herds, although this was unlikely to have a significant effect.

However, those figures were also suspended pending investigations.

The latest figures for cattle slaughtered because they had TB or had been directly in contact with the disease were still published and showed 27,474 animals were killed between January and October 2013, compared to 31,143 during the same period in 2012.

Dominic Dyer, policy advisor for wildlife charity Care for the Wild, said the announcement undermined the Government’s justification for its badger cull policy.

The overstated figures had misled everyone about the extent of bovine TB in the UK when the number of cattle slaughtered because of TB had dropped by more than 11 per cent on last year’s numbers.

Earlier in the week it was revealed that policing costs for the Gloucestershire badger cull were £1.7m and in Somerset £738,985 – both of which would be claimed back from the Government. The Association of Chief Police Officers (Acpo) originally estimated total policing costs would be around £500,000 per year.

In Gloucestershire 921 badgers were killed at a policing cost of £1,850 per badger.

In Somerset 940 cost £786 each.

Defra said the costs were vastly outweighed by bovine-TB’s impact on farmers and taxpayers. Each bovine TB outbreak costs an average £34,000. If left unchecked it would cost the taxpayer £1bn over the next ten years.