Guinea pigs are highly social rodents used in immunology, nutrition, and hearing research. Their welfare requires social housing, which many facilities still fail to provide adequately.
Guinea pig welfare in laboratory settings is compromised primarily by solitary housing and barren environments. As obligate social animals, guinea pigs kept alone cannot express the social vocalisations, huddling, and mutual grooming that are central to their social lives. Isolation causes chronic stress indicated by elevated corticosteroids, reduced immune function, and stereotypic behaviour. Swiss regulations requiring social housing for laboratory guinea pigs demonstrate that this welfare provision is operationally feasible without compromising research. Supplemental vitamin C, appropriate temperature management, and provision of hiding places address additional species-specific welfare needs. The 3Rs framework requires that guinea pig research be replaced with non-animal models where possible, and that when guinea pigs are used, social housing and species-appropriate environments are provided as standard.