I'd just bring them in. I'm a pretty experienced guinea pig owner and I really wasn't comfortable even treating the skin cysts on my skinny pig (one I could see really well). They'll also be able to tell if it's something more serious than a cyst. If it's a cyst, they'll be able to lance it hygienically. If the question is about whether they see guinea pigs, I'm a client and they absolutely do. All the vets are great.
Good animal hospital for all pets tnx all staff for my bird
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