Transporting horses in trailers and horseboxes involves significant welfare considerations related to posture, balance, duration, and loading stress.
Horse transport welfare is well-studied and actionable. The evidence that rear-facing transport reduces physiological stress is clear and practical - rear-facing trailer designs are commercially available. Loading training using positive reinforcement can transform a stressful experience into a manageable routine, with significant welfare benefits for horses transported regularly. Adequate ventilation prevents respiratory challenge; appropriate bedding provides secure footing; access to forage during transit reduces digestive stress. The welfare of horses being transported long distances for slaughter - often showing extreme stress in investigation footage - represents the most serious end of a welfare spectrum that begins with routine competition travel.