Welfare science for guinea pigs, covering their mandatory social housing requirements, dietary needs, and the health conditions that commonly compromise their wellbeing in captivity.
Guinea pig welfare is frequently compromised by fundamental misunderstanding of their social and dietary needs. These animals are obligate social species — the scientific evidence for their social requirement is strong enough that Switzerland has legislated single housing as a welfare violation. Guinea pigs in isolation show elevated stress hormones, reduced activity, and immune suppression that compromises health and lifespan. Yet single guinea pig housing remains common in many countries, driven by the misconception that they are simple, low-maintenance pets suitable for individual keeping. Dietary management is equally critical and frequently incorrect: guinea pigs require unlimited fresh grass hay as their primary dietary component for gut motility and dental wear, with vitamin C supplementation essential through fresh vegetables since they cannot synthesize their own. Many commercial guinea pig diets are inadequate, and reliance on pellets without hay or fresh vegetables causes chronic dental and digestive disease. The health consequences of incorrect guinea pig care are severe and expensive: malocclusion requiring specialist dental procedures, gut stasis requiring emergency veterinary treatment, and scurvy from vitamin C deficiency are all common presentations of welfare problems that proper husbandry prevents.