Unlimited grass hay is not just recommended for guinea pigs - it is essential to their physical health, dental maintenance, and psychological wellbeing. Understanding why matters for proper care.
The most common welfare failure for pet guinea pigs is insufficient hay. Many owners feed primarily pellets and vegetables, not realizing that hay is the dietary cornerstone. Without constant access to hay, guinea pigs face dental overgrowth, painful gut stasis, obesity from pellet overfeeding, and behavioral frustration. Providing hay in abundance - filling a hay rack so it is always available - is the single most important welfare action for guinea pig keepers.