The track veterinarian shall maintain a list to be known as the veterinarians list upon which he shall enter the name of a horse which he considers unfit, unsound or not ready for racing. A horse, the name of which is on the veterinarians list, shall be refused entry until the track veterinarian removes its name from the list. A trainer may appeal to the stewards a decision to place a horse's name on the veterinarians list.
58 Pa. Code § 163.453
This section cited in 58 Pa. Code § 163.456 (relating to scope of veterinarian's list).