The change is part of the "privatisation" of testing for Transmissible Spongiform Encephalopathies such as BSE (Mad Cow Disease). The Department for Food, the Environment and Rural Affairs (Defra) will pay for laboratory work but will no longer pick up the £36m-a-year bill for collection of all animals over 24 months old.

In a compromise hammered out with NFU and National Beef Association, Defra has written off some bills which would otherwise have passed down to farmers and has paid £2m towards the set-up of a new collection network for animals wanted for testing, to be organised by the state-supported National Fallen Stock Company as it moves to independence.

Farmers will have to start paying for the service early next year – probably around £100 an animal, and possibly more the year after, although by then the threshold for testing may have risen to 48 months, by EU agreement.

A list of approved contractors will follow later.