MARTIN, Tenn. - The Professional Racking Horse Trainers' Horse Show scheduled for April 3, in Martin, Tenn., has been postponed.  Tentative plans are to reschedule later this year. This show will have both walking and racking classes and will be at at the West Tennessee Ag Pavilion, University of Tennessee at Martin in Martin, Tenn. For further information, contact Barbara Johnston at 931-762-4485.