Due to the recent detection of equine herpesvirus in three horses at Turfway Park, nearby River Downs has implemented procedures that must be followed before horsemen can ship in to their stalls or use the track for training purposes.The backstretch at the Ohio racetrack opens March 29. River Downs is located about 20 minutes across the Ohio River from Turfway."Every horse that plans to enter the grounds will have to have a veterinarian-approved health certificate noting the horse's temperature within the last 24 hours," said River Downs racing secretary Ed Vomacka, who currently serves in the same position at Beulah Park. "While it may be an inconvenience to some horsemen, they should surely understand that it is a precaution we are taking to protect the entire equine community on the backstretch."Fever and an upper respiratory infection are the most common signs of EHV-1 infection. Commonly, horses have depression, poor appetite, nasal discharge, and cough. Typical transmission from horse to horse is by close direct contact or contact with infected nasal discharge. The virus is short-lived and very susceptible to disinfectants in clean environments.Live racing begins at River Downs April 12. The 122-day meet will run through Labor Day, Sept. 1.