Q: Why cull badgers?

In 1971, the first case of bovine tuberculosis (TB) in a badger was detected on a farm in Gloucestershire. Farmers have since become convinced that the spiralling badger population is to blame for the spread of the disease.

Q: Where are the disease hotspots?

Bovine TB is concentrated to the Westcountry, West Midlands and Wales. In the South West, 23 per cent of cattle farms were unable to move stock at some point in 2010 due to the disease.

Q: What is the impact?

Nearly 25,000 cattle were slaughtered in England in 2010 because of the disease – and it is spreading. Officials suggest the animal disease will cost the taxpayer £1 billion over the next decade. Each confirmed TB incident in cattle costs on average around £30,000, of which £20,000 falls on compensation from the Government, and the rest on the farmer.

Q: What is the Government's plan?

Two "pilot" schemes to test whether "controlled shooting", carried out by trained marksmen, is effective and humane. If successful – the key will be whether more than 70 per cent of badgers can be killed in a cull zone – the method will be deployed in other hotspots. It will not be a national cull, only in affected areas. Defra plans to issue ten licences each year over four years. This means there will be 40 culling zones in total. The pilots will follow a nine-week consultation on proposed guidance issued to Natural England, who will issue culling licences, and are unlikely until 2013. Other measures to control the disease include routine testing and surveillance, pre-movement testing and cattle restrictions.

Q: What about vaccines?

The Government is to invest £20 million to develop cattle and oral badger vaccines. But Defra said: "It's not certain we'll ever be able to develop and deploy them." An injectable badger vaccine is now available but it is costly to trap and inject badgers.

Q: What are the costs?

Farmers and landowners who apply for licences will pay for them, likely to be around £1.4 million for an average sized cull. They are likely to save £1.3 million over ten years. Farming leaders are setting up limited companies to protect anonymity.

Q: What is the reaction?

Farmers, vets and Conservative MPs have welcomed the announcement. As thousands of badgers are likely to be killed, animal welfare campaigners – notably the Badger Trust and the RSPCA – are furious. A legal challenge is inevitable. Labour, which steadfastly refused to sanction a cull, has dismissed the Government's claims the science justifies a cull.