Hopes for a vaccination to protect badgers against tuberculosis have been dashed after scientists admitted the vaccine may never be perfected.
The government’s Veterinary Laboratories Agency had previously said a vaccine for badgers could be used as a measure to tackle the disease within three years.
But it is understood the project is further behind and that a vaccine may never be properly developed.
The revelation comes as the farming industry awaits a decision from the government on whether it will sanction a badger cull as part of a package of measures to tackle bovine TB in England.
Other steps are expected to include more frequent TB testing in high-risk areas, improvements to pre-movement testing regimes and increased controls in higher-risk herds with a history of the disease.
Insiders say plans for the vaccine have been jeopardised because trials have indicated that administering an oral badger vaccine would prove more difficult than injecting them.
The vaccine has to last long enough to take effect once it has been swallowed, but as badgers’ stomachs are so acidic and can break down food quickly an effective product has yet to be found.
Scientists say finding bait that would only be eaten by badgers and not by cattle – whose TB tests could be affected by the vaccine – was another problem.
DEFRA is understood to be announcing the results of its badger vaccine trials shortly and is expected to concede that an effective vaccine may never be licensed.
A department spokeswoman declined to comment on the claims, which were published in the Western Morning News.
While an injectable vaccine for badgers does exist, catching, injecting and marking badgers as vaccinated is regarded by many as being difficult, making the measure impractical.
A BCG vaccine for cattle has also been developed, but it needs to be validated and licensed before it can be used in the UK.
The cattle vaccine faces further problems in Europe as TB-vaccinated cattle and their carcasses are currently banned by the European Union.
New legislation would have to be passed in Brussels before the vaccine could be put to use in the UK.
Farmers Weekly has set up a dedicated channel for all stories connected to proposals for a badger cull.
Don’t let your opinion go unheard – have your say on this topic on the FWi forums.