Livestock virus found on 1,500 farms
A virus that causes stillbirths and birth defects in lambs and calves has spread to more than 1,500 UK farms, new government figures show.
Cases of Schmallenberg have now been reported in all the counties of England and Wales, and in Northern Ireland.
Scottish farmers are on alert for the disease, which is carried by midges.
Some farms have suffered heavy losses of newborn lambs during the winter lambing season.
The latest figures from the Animal Health and Veterinary Laboratories Agency show the virus has been detected on 1,531 farms, in cattle, sheep, alpacas and goats.
Joanne Pugh of the National Sheep Association told BBC News: "It's incredibly high impact for the flocks that have had it and had massive losses.
"But as an overall picture across the whole sheep flock it's a low impact disease."
She said the effect of Schmallenberg (SBV) on individual farms could be devastating, causing much hardship for farmers.
"It's never been a more important time to buy British," she added.
Several animal health bodies, including the National Sheep Association, are trying to gather more data on SBV from the farming community.
The existing data is considered to be a vast underestimate as SBV is not a notifiable condition and there is only limited testing of animals.
A vaccine for SBV is being developed but has not yet been approved for use in the UK.
The Veterinary Medicine Directorate (VMD) said it was considering data on the vaccine but it was not possible to provide an indication of when it might be authorised.
"The VMD recognises the impact on individual animals and farmers a disease such as Schmallenberg can have," it said in a statement.
"The VMD will operate timelines for the remaining stages of consideration of the application mindful of this while ensuring, through our rigorous scientific assessment process, that proper care is taken to ensure that any vaccine is safe for the relevant livestock. "
SBV is spread by biting insects, including midges and mosquitoes.
It takes its name from the German town where it was first identified in 2011.
The disease causes fever, reduced milk yields and loss of appetite in adult cattle.
It can also lead to birth defects and stillbirths in newborn sheep, cattle and goats.
The virus can also infect wild animals, including deer, according to scientists.