All meetings across the UK on Thursday have been cancelled due to an outbreak of equine flu.
Three horses, who had been vaccinated against the disease, tested positive having raced on Wednesday.
The British Horseracing Authority has cancelled Thursday's meetings in response.
Horses from the infected yard have raced today at Ayr and Ludlow, potentially exposing a significant number of horses from yards across the country and in Ireland. The fact that the cases have been identified in vaccinated horses presents a cause for significant concern over welfare and the potential spread of the disease and the action to cancel racing has been viewed as necessary in order to restrict, as far as possible, the risk of further spread of the disease.
The BHA has worked quickly to identify which yards could have potentially been exposed today and identify the further actions required. The BHA is presently communicating with yards potentially exposed to ensure appropriate quarantine and biosecurity measures are put in place and horse movements restricted to avoid possible further spread of the disease.
The full extent of potential exposure is unknown and we are working quickly to understand as much as we can to assist our decision making. The BHA is working closely with the Animal Health Trust and will issue a further update tomorrow. We recommend that any trainer who has concerns about the health status of any of their horses should contact their veterinarian.
More to follow.