Mo. Rev. Stat. § 313.680: Names of horses — registered name required to be used, penalty.

1. No individual shall knowingly enter or cause to be entered for competition any horse under any other name than its registered name, or out of its proper class, for any purse, prize, premium, stake, or sweepstakes offered to the winner of a contest of speed at any race meeting held by a race track licensee.

2. The name of any horse, for the purpose of entry for competition in any contest of speed, shall be the name under which the horse has been registered and has publicly performed.

3. Any individual convicted of violating the provisions of this section shall be guilty of a class B felony.