Bovine TB is found in both badgers and cattle
Badger culls are unlikely to be a cost-effective way of controlling bovine tuberculosis in cattle, a report warns.
The Imperial College London and Zoological Society of London report comes ahead of a controversial cull in west Wales planned for later this year.
The report, which studied the aftermath of cull trials in England, claims the benefits "disappear" after four years.
But Wales's chief vet said the approach would differ to include a limited badger cull and strict cattle controls.
The report, commissioned by the Department of Environment and Rural Affairs (Defra), says benefits from widespread badger culling are not sustained three-and-a-half years after a cull has ended.
It also says "patchy," and "unco-ordinated circumstances" are highly likely to increase rather than reduce incidences of bovine TB in cattle.
The report focuses on the Krebb trials, which took place in England between 1998 and 2005. It questions if the financial benefit seen after culling is worthwhile.
Bovine TB is a disease in cattle that has a serious financial impact on farmers in Britain, as infected animals have to be slaughtered.
In 2008, 2,738 herds were infected with bovine TB, costing the government more than £100m.
Badgers and cattle are the main source of bovine TB in the UK.
Because of this, UK governments have tested various means of badger culling to control infection in cattle over the past 30 years.
The environment secretary decided against badger culling to control cattle TB in England in 2008.
However, the Welsh Assembly Government now proposes to implement a badger cull, though it faces a legal challenge to this proposal.
Prof Christl Donnelly, senior author of the study from Imperial College London, said: "Bovine TB is a big problem in Britain and the disease can profoundly affect farmers' livelihoods.
"We know that it is transmitted between cattle and badgers, so the randomised badger culling trial was set up to find out if culling badgers would help control the spread of the disease.
"There has been some controversy over badger culling as a bovine TB control method and it has been unpopular with the general public.
"Although badger culling reduced cattle bovine TB during the trial and immediately thereafter, our new study shows that the beneficial effects are not sustained, disappearing four years post-cull."
Prof Donnelly said the research also suggested the savings farmers and the government would make by reducing bovine TB infections in cattle were two or three times less than the cost of repeated badger culls as undertaken in the trial.
"This is not a cost-effective contribution to preventing bovine TB infections in cattle," added Prof Donnelly.
However Dr Glossop, chief veterinary officer for Wales, said the report's findings that badger culling alone would not solve the TB problem came as no surprise.
She added the Welsh approach would not be the same as that in the trial culls.
"What we are proposing is to combine a limited cull of badgers with strict cattle control measures within a defined area over a sustained period," said Dr Glossop.
While she said there were similarities to the culling trials, she added: "The differences are so significant to prevent true comparison of the results and we are confident of a much longer-term success rate as a result.
"In the last 10 years we have spent almost £100m on compensation alone in Wales. We can't let this situation continue unchecked."