The level of bovine tuberculosis in cattle has fallen across Great Britain in the first five months of 2014, Defra figures show.

The number of new herd incidents during the period January to May 2014 was 2,136 – 3.4% lower than the figure of 2,211 for the same period in 2013.

During the first five months of 2014, 14,413 cattle were compulsorily slaughtered to control the disease compared with 15,246 a year earlier.

A Defra spokesman welcomed the improved figure but urged caution in reading too much into the statistics because there were unclassified incidents still to be accounted for.

“It’s important that we don’t overplay the recent statistics,” the spokesman said.“There is still a long-term trend that has seen TB increase over the past decades. That trend needs to be reversed, which we are still far from achieving.”

See also: Video: TB-infected cattle shot dead on farm

“We clearly cannot be complacent, especially as bovine TB continues to spread geographically, posing a major threat to yet more farmers across England,” he said.

In Wales the number of cattle slaughtered showed a slightly steeper rate of decline with figures indicating a 5% reduction from 3,179 cattle in 2013, down to 3,013 from 1 January to 1 June.

The Welsh government also highlighted figures comparing TB levels for the 12 months up to May 2014 with the previous year.

These statistics show 826 new incidents of bovine TB in Wales from June 2013 to May 2014 compared with 1,009 between June 2012 and May 2013.

This represents an 18% decrease for the 12-month period, the Welsh government said.

Despite the better results, Welsh deputy farm minister Rebecca Evans adopted a similarly cautious approach to the Westminster government.

“Bovine TB continues to be one of the biggest problems facing the farming industry in Wales. It is a devastating disease and one that as a government we are working hard to eradicate,” Ms Evans said.

“Whilst we know that disease figures can fluctuate from month to month, these latest statistics continue to indicate a downward trend for bovine TB in Wales and this is very encouraging news,” she said.

And NFU deputy president Minette Batters said: “The fall in the number of new herd incidents between January and May this year, compared with the same period last year, will be welcomed by all farmers living with the threat of this disease, as will the news that fewer cattle were compulsorily slaughtered over the same period.

“But the fact that more than 2,130 new herds went down with the disease during the first five months of this year, and 14,413 cattle had to be slaughtered, shows that TB is still a huge issue for our livestock and dairy sectors and continues to devastate farming family businesses.”

She added: “We have always said that we need a comprehensive strategy to deal with this disease in areas where it is endemic and to stop it spreading any further. In these areas it’s too late for badger vaccination because it won’t cure a badger that’s already sick, so control of the disease in badgers in these areas has an essential role to play in stopping reinfection occurring.”

Ms Batters also said that it was vital the disease was not allowed to spread further. “That is why we support badger vaccination in the edge and clean areas and are working with Defra and other groups on the development of a badger vaccination project to help stop the disease spreading,” she said.

“It’s crucial too, that everything is done to speed up the development of a useable cattle vaccine.

“The government’s TB eradication strategy looks at using every tool in the box to eradicate this disease. Tackling the disease on all fronts, along with significant investment in research to improve diagnostics, is crucial if we are going to beat this disease and achieve our goal of a TB free England.”

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