DEFRA is assuring worried horse owners that it has traced all equines that came into contact with the horses with swamp fever in Wiltshire last month.

Owners in Wiltshire closest to the yard on which the swamp fever cases were discovered have been concerned at the number of equines which may have been in contact with the EIA-positive horses.

The owner of the yard has not yet been officially named, but widespread speculation suggests he is a large-scale dealer and that many hundreds of horses pass through the yard each month.

But a Defra spokesman told H&H this morning: “All in-contact horses from the EIA (equine infectious anaemia) cases have been traced and have undergone initial tests.

“These were all negative, but obviously they need to undergo two more tests — at 30 and 60 days.”

He could not confirm this morning whether any more premises in the UK are in isolation — or how many horses have been tested.

The spokesman also said that Defra has been investigating implications to the case of swamp fever found in a horse in Belgium since the end of last week.

He said two horses have been traced in Britain that possibly came into contact with the diseased animal before Christmas.

“These have also tested negative at this stage, but further tests are pending,” he added.