Researchers say the number of Bovine TB cases is rising

The number of cases is rising by 18% a year, with more than 22,000 infected cattle culled last year, researchers at Exeter University say.

The study assessed nearly 100 farms in south-west England hit by Bovine TB.

Infected cattle, or those suspected of infection, must be slaughtered and movement of animals is restricted.

Controls also mean that farmers are prohibited from trading animals freely.

Farming stress

These safeguards can last for years leading to annual losses of tens of thousand of pounds.

However, restrictions following the foot-and-mouth outbreak four years ago only lasted for 12 months.

The report says 20% of calls to rural stress helplines are from farmers affected by the disease.

Martin Turner, who led the research team, told BBC Radio 4's Farming Today that the situation could get even worse.

The National Farmers Union is now pressing harder for a controversial cull of wildlife, including badgers, to start as soon as possible.

'Profound consequences'

South-west director Anthony Gibson said the number of farmers diversifying away from cattle to reduce the risk to their businesses was on the increase.

"This is a trend which, if it gathered momentum, would have profound knock-on consequences for many other rural businesses," he said.

The best answer to the problem was to eliminate Bovine TB by "dealing with its reservoir in the wildlife population - principally diseased badgers".

But conservationists say there is not enough evidence to support the theory that badgers help spread the disease to cattle.