Britain's turkey farmers are preparing against a disease which could potentially decimate their Christmas stock.
The liver disease blackhead could be heading to the UK
It is feared the liver-damaging disease blackhead, which has already attacked flocks in Germany, France and the Netherlands, could be heading towards the UK.
The drug Emtryl used to be added to turkey feed to provide protection against the disease, but this was withdrawn by the European Union in March this year, amid fears it may cause cancer in humans.
Farmers say they now have no control against the disease other than hygiene measures, and are simply hoping it does not reach the UK.
Farmer John Garner, of Godwick Hall, Norfolk, said he was "extremely worried" about his 600-strong flock of free range bronze turkeys.
Mr Garner told BBC Radio 4's Farming Today: "Blackhead has been around for many, many years, but we've never seen it simply because we've had this marvellous drug Emtryl that has been added to the feed for years and years and years.
"If we got an outbreak it would be extremely serious. There is nothing else to control this disease, absolutely nothing.
"I gather that the mortality rate, particularly in young turkeys, is 100% and that's total financial loss," he said.
'Holding our breath'
David Kelly, who runs Kelly Turkey Farms in Danbury, Essex, called on the EU
to overturn the decision.
"At the moment there is a potential threat to the Christmas supply," he
"We're within a few weeks of the killing so we are just holding our breath
and hoping we don't get it."
The disease, also known as histomoniasis, is caused by a parasite which lives in earthworms, and can stay in the soil for long periods of time.
It enters the birds' guts and attacks
their livers, turning their blood blue and making their heads darker.
As it lives in the soil, it poses the biggest threat to high-end, outdoor-reared turkeys.
Turkeys often waste away within seven or eight days, but the disease poses no threat to humans.
Mr Kelly has introduced routine worming for his 100,000 free-range flock, while Mr Garner is making sure nobody accesses his birds other than him.
Other farmers are taking measures such as putting foot baths outside gates, and storing turkey feed securely.
But they say they can do nothing to stop migrating birds carrying the disease to the UK.
However, the National Farmers' Union said it was "confident" these hygiene measures would be sufficient and the Christmas supply would not be affected.
NFU chief publicity officer Peter King said the risk of blackhead spreading in the UK was low.
He said: "In the absence of Emtryl, routine worming systems have been introduced that provide good protection."
He also stressed the importance of other hygiene measures including stringent bio-security and cleaning footwear entering and leaving farms.
The Department for Environment, Food and Rural Affairs supports the ban on
Emtryl, but has urged the drug's manufacturer to provide the EU with more
information which it believes could lead to the decision being reversed.
Ten million turkeys are being bred in the UK for this year's Christmas season.