Government claims that badger culling is needed to tackle tuberculosis in cattle based on successes in other countries are "seriously flawed", a group of vets has said.
Ministers warn that no country in the world with TB in wildlife has eradicated the disease in cattle without controlling it in wild species, pointing to programmes in places such as New Zealand, Ireland and the US.
But in a letter to the Veterinary Record, 19 vets raised concerns about the claims, saying that very few countries had needed to kill wildlife as part of TB control programmes.
In New Zealand brush tail possums have been targeted to tackle TB, but the species is not a native breed, has caused significant problems for other wildlife and has very different habits and social structure to badgers, the vets said.
White tail deer were culled in the US, but had only become part of the TB problem when hunters started winter feeding of the animals to make them more available for hunting, which brought them into close contact with other deer and cattle, they said.
Questions have been raised about the contribution widespread killing of badgers has made in Ireland after it emerged that there were similar declines in TB in cattle in Northern Ireland, where culling has not been used.
"The premise that badger killing can be justified on the grounds that wildlife controls have been deemed necessary in other countries in order to control TB in cattle is seriously flawed," the group wrote.
The vets said the efficacy of "indiscriminate" culling of badgers to control TB in cattle was not supported by scientific evidence, with research showing that surviving badgers moved around more, potentially further spreading the disease.
They warned that the methods being used to kill badgers in the two pilot culls in west Gloucestershire and west Somerset were very different from those employed in the long-term trials which form the scientific basis for the Government's policy.
The "controlled shooting" of free-running badgers employed in the pilot culls was deemed to be ineffective and inhumane by an independent panel of experts which evaluated the schemes.
The vets, who include TV vet Marc Abraham and Humane Society International UK's executive director Mark Jones, said research had shown the benefits of vaccinating badgers and that strict cattle testing and measures could bring the disease under control without culling.
They wrote: "Many mammal species can become infected with bovine TB, and badgers are undoubtedly capable of carrying and transmitting the infection.
"However, attempts to control bovine TB in cattle by killing badgers have been repeatedly shown to be ineffective, cruel and unnecessary.
"In supporting efforts to resolve this situation, we as a profession must not succumb to advocating the apparent 'easy fix' of inhumane and indiscriminate badger killing when it has no basis in science and, as such, is not ethically justifiable," the vets said.
Caroline Allen, Green Party animals spokeswoman, a working vet and a signatory of the letter, said: "There are so many flaws in the arguments that culling badgers is the answer to bTB.
"There is now so much evidence against badger culling being either effective or humane it beggars belief that the Government is still considering it as an option.
"It is clear that they will quite rightly face intense public and political opposition if they continue to try and kill badgers, either though shooting or gassing. The Green Party will continue to oppose all killing of badgers."
A spokeswoman for the Environment Department (Defra) said: "No country in the world where wildlife carries TB has successfully controlled the disease in cattle without tackling its presence in wildlife as well.
"Culling of feral and wildlife reservoirs to tackle bovine TB, combined with cattle measures, has been successful in Australia and is working in New Zealand and the Republic of Ireland too.
"Along with biosecurity measures and cattle movement controls, culls will help get TB under control."
British Veterinary Association (BVA) president Robin Hargreaves said: "While some countries have successfully eradicated bovine TB without culling wildlife, this was only possible where the disease was not endemic in local wildlife populations.
"The randomised badger culling trials (RBCT) established beyond any doubt that badgers play a significant role in TB in cattle in the UK, and unless we tackle the disease in badgers, we will never eradicate it.
"There is no evidence that badger vaccination in high-incidence areas leads to a reduction in TB in cattle. In contrast, we know from the RBCT that culling does.
"However, BVA does see a role for badger vaccination as part of a comprehensive eradication strategy, particularly in 'edge' areas, but its limitations mean it is not an alternative to culling in high-incidence areas."
He added: "We are acutely aware that culling is not an 'easy fix' but our members are committed to tackling bovine TB and its devastating impact on cattle herds, wildlife, and farming communities.
"Our position supports the use of effective, targeted and humane badger culling as part of a comprehensive package of measures."