FRANKFORT, Ky. (AP) - Gov. Steve Beshear has signed an emergency regulation immediately banning steroids for Kentucky's thoroughbred and standardbred races.

The new rules ban anabolic steroids from being present in the blood of any horse that's racing. Horse regulators approved the sweeping ban earlier this month.

Beshear spokesman Jay Blanton says the ban was in effect as of Friday. A 90-day grace period is in effect for any horses who were given steroids before the ban went into effect.

Three specific steroids could be given for therapeutic purposes at the request of a certified veterinarian, and even those horses would be prohibited from racing without proof that they've been off the drugs for 60 days. First-time offenders will be suspended for up to 60 days.