Horses are highly social animals whose welfare is severely compromised by solitary keeping, a practice that remains common in domestic settings.
Horses evolved to live in stable social groups and experience genuine psychological distress when isolated. Solitary confinement causes separation anxiety, stereotypies like crib-biting and weaving, and chronic stress that affects health and behavior. The common practice of keeping individual horses in separate stables with only brief social contact prevents natural social bonding and play. Horses should be viewed as requiring companions as a fundamental welfare need, not a luxury.