Guinea pigs are highly social prey animals with specific needs for companionship, space, and appropriate housing that are frequently not met, making them one of the most welfare-compromised companion species.
Guinea pigs are frequently purchased as starter pets without adequate understanding of their needs. The combination of social requirement, space need, specialist diet, and veterinary costs makes them more demanding than typically recognised. Solitary guinea pigs suffer from the absence of conspecific company that is fundamental to their social nature. Inadequate housing prevents running, which is important for cardiovascular health. The contrast between perceived simplicity and actual welfare requirements makes guinea pig ownership a significant welfare concern.