unsure about burst lump on back

Question
Our guinea pig, Brownie-Mo, got a lump on his back about 2-3 months ago. We took him to the vet, and he said it could be a cyst, an abscess, or a tumor. He said to leave it, and see if it grew. Also, Brownie-Mo squealed a bit, while he felt it, and it might have caused him pain. So we left it, and I just discovered it has burst open. It has no pus, or any fluid in it, but it doesn't look very pleasant, it almost looks like a small hole in his back, with a sort of fungus, or something in it. I am very unsure what exacly it is, and I need to know how to treat it.

Answer
Hi Kezia,

Sorry for the delay in getting back to you. I have had increasingly problematic issues with my internet as well as having a very busy home life (newborn twins), so I have had delays in responding to all questions in the past two weeks. Apologies if any inconvenience was caused.

First of all, I have to say I love your guinea pigs' name, Brownie-Mo. Excellent choice and I'm sure it suits him!

As far as the burst lump goes, I highly recommend you contact your vet. You want to get professional advice and safe medication to prevent infection as soon as possible, as the area will be susceptible to such problems now it's so "open".

Good luck, and again I'm sorry for the delay.

Best Wishes,

- Laura
www.cavy-care.com