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.
Copy the kind of date as well as the date
A date without its meaning is easy to misread. Manufacture, purchase, opening and best-before describe different events. The label-context note can hold the words already printed on the existing package without inventing a missing manufacture date or a purchase history.
The references use different clocks
PDSA describes using pellets within three months of purchase. VCA describes ninety days from manufacture. RSPCA UK refers to the best-before date and freshness. These are not the same starting point. This site does not calculate one universal expiry date by averaging them.
Storage matters without becoming a laboratory
The sources describe vitamin C becoming less stable over time and with storage conditions. A sentence about a cool cupboard cannot measure nutrient content. The form does not inspect humidity, test food, determine spoilage or certify an opened bag as safe.
An unknown date should stay unknown
Do not estimate an opening date to obtain a reassuring output. Keep the missing label or storage detail visible and ask the current manufacturer or veterinarian when needed. This page is not a discard calculator or permission to feed an uncertain product.
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