Courtesy of Google AI:
In National Hunt (NH) jump racing, a toe board at the base of a hurdle or plain fence serves as a visual take-off guide and ground-line indicator that helps the horse spot the obstacle and judge where to jump. (Ref: Irish Horseracing Regulation Board)
Visual Cue: It provides a clear, low-level line of sight so the approaching horse can accurately index the start of the jump rather than misjudging the shadow or dimensions of the barrier. (Ref Easyfix Equine)
Take-Off Accuracy: By marking the precise ground line, it encourages the horse to take off at the correct distance from the obstacle.
Modern Design: Newer padded and artificial hurdles (such as those by EASYFIX Equine) integrate high-impact plastic toe boards angled around 60 degrees, which also assist ground staff in setting the correct angle and maintaining safety and consistency across the flight. (Ref: Easyfix Equine)