The Illinois State Fair has postponed Monday's harness races because of unfavorable track conditions.
The races will now be run Wednesday starting at noon.
Nearly three dozen horses were quarantined briefly over the weekend because of concerns they may have been exposed to a virus.
The (Springfield) State Journal-Register reports that officials lifted the quarantine Saturday, after the animals were cleared of having the equine herpes virus.
The concern followed reports that a horse began exhibiting symptoms at Balmoral Park in Crete and had shared quarters with six other horses brought to Springfield.
But a spokesman for the fair, Jeff Squibb, says tests conducted on the sick horse came back negative, making the measures no longer necessary. Squibb says there's no threat of the virus to humans.