Scientific evidence on horse social needs demonstrates that appropriate social contact with conspecifics is a fundamental welfare requirement, not an optional enrichment.
Horse social welfare science has produced clear evidence that social isolation causes significant chronic stress and psychological suffering. The common management practice of individual stabling without visual or physical access to other horses represents a significant welfare compromise given this evidence. Gradual group introduction with appropriate space and resources reduces injury risk during integration. Stable contact through shared fence lines provides partial social benefit but does not fully substitute for social interaction. Management systems that enable at least visual contact with other horses as a minimum standard, progressing to appropriate social grouping where resources allow, represent evidence-based welfare improvements accessible to most horse managers.