Can guinea pigs eat butternut squash skin?

Guinea pigs can eat butternut squash skin in small amounts, but it should be given with caution. The skin is tough and may be difficult for them to digest, so it's best to peel it and offer only the flesh of the squash. Always introduce new foods gradually, and monitor for any signs of digestive upset. Fresh hay, vegetables, and a limited amount of fruit should make up the majority of their diet.