Pet Preserver

dressings of wood pet safe?
Ok, so I will build my guinea pigs a new cage and run. I wonder what preserver Wood / dressing is safe to use. I obviously do not want to get sick or die from chewing! I'm in the UK, so the links / stores purchase would be good.
I used to have a branch of an apple tree, not like that because it is sweeter than other types of wood, and safe to eat. Do not let them to chew their cage, which was made of cedar. You do not need an additive or dressing. I do not use anything that has been exposed to chemicals. Make sure you know where the wood, wood came from and whether it was tainted or not. You could ask the hardware store about the best kind. Good luck
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