Farmers were on alert last night after the H5N1 strain of avian flu was confirmed in three dead wild swans in Dorset.

A three-kilometre wild bird control area and a 10-kilometre monitoring area have been enforced by Defra around the Abbotsbury Swannery, near Weymouth.

“Our message to all bird keepers, particularly those in the area, is that they must be vigilant, report any signs of disease immediately, and practice the highest levels of biosecurity,” said acting chief veterinary officer, Fred Landeg.