The stables of Nigel Twiston-Davies (pictured) have been shut down following the death of two horses from an outbreak of the highly infectious equine herpes virus.

The trainer is unlikely to be able to resume operations for about a fortnight and there must be a doubt about his Grand National winner Bindaree defending his crown at Aintree on 5 April.

Twiston-Davies had two runners at Cheltenham on Tuesday and the boxes used by those horses have been locked up and will not be used for the duration of the meeting.

Peter Webbon, the Jockey Club veterinary officer, said that all 50 horses in the yard had been blood-tested after Cresswsell Cherry and Joyeuse had been put down on Tuesday when they had become paralysed in their hind legs.

The entire string has been isolated into smallgroups and all the horses are going to be re-tested at the weekend. Twiston-Davies said he is confident that Bindaree will make it to the National.

“The horses that have been affected were in adjacent boxes and looked after by the same girl, whonever goes near Bindaree,” he explained. “So unless Bindaree has it on him already, and there is no sign of that, there should be no hold-up.”