Guinea pigs are social prey animals with complex behavioral needs that are often underestimated by owners, leading to widespread welfare problems in captivity.
Guinea pigs kept alone suffer chronic loneliness that manifests as lethargy, repetitive stereotypic behaviors, and reduced health. Single guinea pigs often live shorter lives than those kept in compatible pairs or groups. The common practice of keeping guinea pigs in small cages prevents natural movement, grazing, and social interaction. Vitamin C deficiency causes scurvy — painful joint swelling, dental disease, and immune suppression — when diets rely on pellets lacking adequate vitamin C. Heat is a serious danger that is often underestimated in warm climates.