Preliminary tests on a bull showing symptoms of foot-and-mouth disease at a farm in Cornwall have proved negative.

The farm, at St Cleer, near Liskeard, had been cordoned off as a precautionary measure after a bull showed possible signs of the disease.

Samples from the farm were sent for urgent tests at the Institute for Animal Health laboratory at Pirbright in Surrey.

The Department for the Environment Food and Rural Affairs (Defra) has imposed a complete ban on livestock movements within 8km (5 miles) while more detailed investigations are carried out.

It looked very like foot-and-mouth, but the lesions weren't typical of the disease

Jan Kelly, Defra

The movement restrictions were imposed because the bull was found to be showing signs of a condition which vets "could not rule out" as being foot-and-mouth disease.

There have been a number of false alarms since the last confirmed case of foot-and-mouth on 20 September 2001.

Jan Kelly, Defra's veterinary manager for Cornwall, said the owner of a pedigree bull breeding unit contacted a vet on Saturday after one animal became ill.

Vets were called to the same farm on Monday after the animal's condition worsened.

Definitive answers

Mrs Kelly said: "On Monday afternoon the vet had a look at the animal's tongue, which was shredded.

"It looked very like foot-and-mouth, but the lesions weren't typical of the disease."

Although the initial results have proven to be negative, definitive answers from laboratory tests can take up to 96 hours, Defra said.

The National Farmers' Union (NFU) is continuing to warn its members not to panic.

Ian Johnson, the NFU's South West spokesman, said earlier on Tuesday: "We must try to put this in perspective.

"Obviously vets have been very diligent and there may be other problems which cause similar symptoms.

'A major blow'

After its initial outbreak in February 2001, foot-and-mouth disease took just two weeks to spread across Britain.

The final number of confirmed cases reached more than 2,000 and millions of animals were destroyed.

Earlier this month, the European Commission said vaccination should be used to tackle any future outbreak.

The UK Government had gone against the advice and dealt with last year's crisis by mass slaughter.