Horses are highly social animals for whom social isolation causes measurable psychological distress and behavioral problems, yet single-horse keeping remains common in many management systems.
The welfare cost of social isolation for horses is substantial and well-documented, yet single horse keeping remains common due to space constraints, owner inexperience, and underestimation of the social nature of these animals. A lone horse at home without visual contact with other horses may spend hours in a state of heightened anxiety, particularly when left alone by owners. This chronic stress manifests as stall weaving, cribbing, wood chewing, and other stereotypies that are often incorrectly attributed to boredom rather than social deprivation. The welfare standard should be same-species companionship as a minimum, with direct social contact preferred over mere visual access. Where same-species companions are not possible, cross-species companions provide meaningful but partial welfare improvement.