Scientists are in a race against time to wipe out foot and mouth - and may have to utilise cloning techniques to create a "Jurassic Farm" which could prevent rare breeds becoming extinct in Yorkshire.

Plans are underway to set up a "gene bank" of DNA extracted from threatened species of cows and sheep so that the breeds can be cloned and survive should the disease take hold and wipe them out - a more rustic version of the hit film where boffins bring dinosaurs back from the dead in just the same way.

Surely the plan is just Spielberg-esque science fiction? Sadly not, and neither is the very real deadline the Government has set itself to get foot and mouth under control.

Although it may have left the headlines, it's a battle that is still being raged in the Bradford district. Last month a herd of 131 dairy cattle were slaughtered at Silsden because the farm was considered "a dangerous contact". At the weekend a herd of sheep were culled in Baildon.

As cases continue to crop up in West Yorkshire - the number in the Settle and Skipton area now tops 96 - the man in charge of the battle against the disease issued a stark that unless foot and mouth is conquered in the next few weeks, the situation could be worse than ever.

David King, the Government's chief scientific officer, told a gathering of ministers that the foot and mouth virus hates hot conditions, so unless it is beaten by the time summer ends, while it remains at its weakest, it could return with a vengeance in the wintry conditions it thrives under.

He said: "An epidemic in Greece was wiped out by three days of 40 degree C weather. We have only the summer months. If it drags on into winter, it may persist even longer."

Should that happen, it could see a return to mass culling of animals and the pyres of burning animal carcasses that blighted the countryside on a regular basis in Spring.

And some species of animal - especially breeds almost exclusive to Yorkshire - could be wiped out by a second assault of foot and mouth.

The Rare Breeds Survival Trust has launched an appeal in London this week to raise £2.5m to expand an existing gene bank.

Chief executive Rosemary Mansbridge said that some breeds of cattle, pigs and sheep have critically low numbers.

Among the hardest hit is the Whitefaced Woodland sheep. Six months ago there were only 500 breeding females in the country, and since the foot and mouth outbreak 100 of these ewes - mostly in West Yorkshire and the Pennines - have been destroyed.

Similarly, the Beef Shorthorn cow, which numbered in the thousands in North Yorkshire and Scotland half-a-century ago, is down to 1,800 breeding cows, with 12 per cent of the population wiped out in the last few months.

Rosemary Mansbridge said: "We have to make sure that we hold sufficient genetic material to ensure that when the next farming crisis hits, we shall not lose any of the 63 unique breeds the charity looks after."

The Whitefaced Woodland sheep is one of several rare breeds at the Bradford City Farm, which remains closed to the public by foot and mouth. Animal worker Emma Chambers, in fact, bottle-reared a Whitefaced Woodland lamb this year, which the farm has named Milo.

She didn't like to think about the prospect of the sheep numbers dipping so low that cloning techniques would have to be utilised. "It's a fairly frightening thought," she said. "Besides, it's not natural, is it?"

But John Gullett of the National Farmers Union in Bradford, currently seconded to the Department of the Environment, Food and Rural Affairs (DEFRA, formerly MAFF) at Leeds, was philosophical about the idea.

He said: "We could well have the situation where rare breeds are being wiped out. Anything that seems sensible or prudent we have to look at."

Mr Gullett agreed with the Government predictions that foot and mouth could take hold even stronger if it was not wiped out by the end of summer. He said: "The general opinion is if we don't get this thing sorted out in the next two months then we are going to have very big problems.

"Just how bad it is going to be... well, how long is a piece of string? We can't say now whether it will be as bad as what we've seen or even if it will be worse."

Mr Gullett said that had the disease been confined to cattle, which show symptoms almost immediately, it could have been contained a lot sooner. But, he added: "Sheep can carry the disease and not show any signs for up to six to eight weeks."

In his recently appointed role seconded to DEFRA, Mr Gullett is fielding calls from farmers in West Yorkshire all day and is ready to speed to sites where the disease is suspected at a moment's notice.

Should foot and mouth return this winter, the Government says it may be the fault of the farmers themselves.

David King said: "We're bumping along at four cases a day with no sign of the epidemic coming under control.

"Random movements of animals, people, and machinery are still spreading the virus."

In an attempt to head off another crisis, King will lead a delegation of vets and ministers to visit hot-spot areas such as the area around Skipton to forcefully remind farmers about disinfecting and "biosecurity" on farms.

It could mean a return to the unpopular "24/48" culling policy - all animals on an infected farm being slaughtered within 24 hours of the disease being reported, plus all animals on farms within three kilometres being culled within 48 hours.

Roy Anderson, the scientist from the Imperial College London is the man who advised ministers to adopt the policy. Speaking at the same ministerial briefing earlier this month in which King warned about the summer deadline, he said: "Without the 24/48 policy, we would be in a very bad situation at the moment."

And he said that the random nature of cases still occurring at the moment "must be down to the movements of people or vehicles".

Mr Gullett said: "We are still advising and helping farmers to be very strict on biosecurity. We also have the problem that some members of the public have ignored directives to stay away from suspect areas throughout this crisis. There are plans at the end of the month to open more footpaths, and in some areas of West Yorkshire I think this is much too early." Bradford City Farm staff member Emma Chambers is pictured cuddling one of the rare breed of sheep under threat from the spread of foot and mouth disease in the area.