Contagious Equine Metritis (CEM) is a notifiable venereal disease of horses in Ireland. Infection spreads through direct transmission of bacteria from mare to stallion or from stallion to mare at the time of mating. It is also transmitted to mares if semen used in artificial insemination (AI) comes from infected stallions.
CEM is a condition that undermines commercial performance and as such, its eradication is primarily the responsibility of the industry itself. CEM infections are treatable with good outcomes. Breeders and veterinary practitioners are advised by the Department to follow the Irish Thoroughbred Breeders' Association and Horse Sport Ireland's Codes of Practice and to ensure that all stallions, teasers and mares are specifically tested and cleared negative for CEM before they are used for any breeding purposes.
As regards the current outbreak, the Department has restricted the premises concerned and a full epidemiological investigation is under way focusing on the infected premises and recently inseminated mares.