The evidence base for horses' social needs has grown substantially, moving from welfare guidance to strong scientific consensus that companion animals are essential for equine behavioral health.
Horse social welfare is no longer a matter of debate in welfare science: social companionship is a fundamental behavioral need whose deprivation causes measurable psychological harm. Horses kept individually show stress indicators, perform stereotypic behaviors at higher rates, and show distress behaviors when separated from familiar individuals. Practical barriers to social housing exist (cost, space, management complexity), but welfare-focused horse keeping starts from the recognition that social companionship is a basic need. Where equine companionship is impractical, alternative companion species (donkeys, goats) provide partial welfare benefit through social contact.