Sources fetched 13 November 2026. PawLine editorial team. Not professionally reviewed.
Guinea pig food education, not veterinary advice. Illness, stopped eating or suspected poisoning needs direct veterinary contact. Difficulty breathing is an emergency. Do not wait for a note or app response. No food clearance or safe waiting time is provided.
Start with the role of hay
PDSA, RSPCA and VCA describe continued access to suitable feeding hay or grass as central to guinea pig care. They connect fibre and chewing with digestive and dental needs. A product with a guinea pig on its front does not replace that broad principle or establish an individual animal’s diet.
A percentage needs a definition
Published guides use descriptions and sometimes percentages, but an unlabeled percentage can lose its basis when copied into a household note. This site does not turn hay, fresh food and pellets into interchangeable weights or calculate a balanced ration from numbers entered by a reader.
Not every use of hay is the same instruction
A food description, a bedding discussion and a medical feeding instruction answer different questions. Keep the original context visible. The note does not select a hay variety for a growing, pregnant or ill animal, identify a plant or approve a batch from a photograph.
Sources and limits
PDSA: Your guinea pigs’ diet, October 2024
RSPCA: A healthy diet for guinea pigs
VCA: Guinea Pigs: Feeding, Gregory Rich DVM; Laurie Hess DVM; Rick Axelson DVM