Confirmed cases of Schmallenberg virus (SBV) have continued to blight the industry and vets have reiterated calls for farmers to submit affected carcases for post-mortem examination.
With lambing in full swing and vets reporting a ’higher number of cases than normal’, they fear the lack of reported cases has blurred the true UK picture of the disease.
It came as SAC Consulting Veterinary Services confirmed two diagnoses of SBV infection in malformed lambs in two Scottish flocks close to the border with England.
Keith Cutler, of the Endell Veterinary Group, Salisbury, said he had never seen so many cases of newborns with foetal deformities.
"The true extent of the problem is not understood."
- Industry statement
He said: “With it not being a notifiable disease there is no compulsion to report it, but the trouble is, unless testing is being done and official figures are released, how do we monitor its prevalence?
“It is very different now we have lost the surveillance networks in veterinary investigation centres.
“Without the over-arching process how is farmer A going to know what is happening with farmer B?”
The industry has already fallen victim to a number of losses from deformed lambs, with the highest numbers reported in Cumbria, Devon, Lancashire and Shropshire.
Total figures show 84 recorded cases in England and a further 25 cases in Wales.
Mr Cutler said farmers must take extra precautions in the future to report any suspected cases.
"It is about farmers having that rational discussion," he added. "They need to think about what else they could or should have done to prevent it."
A joint industry statement said: "We have already heard of a number of cases and mainstream lambing and calving is only just starting. However, the Animal and Plant Health Agency (APHA) has not received many samples so the true extent of the problem is not understood.
"When APHA suspects SBV they will fund the testing.
"Importantly we need to discover the true levels of the virus as this will determine activity later this year, which will seek to inform what action we need to take to protect against SBV going forward."
For more information about SBV, click here.