Spot and lump

Question
hi,my name is Becker and i have two very happy looked after mice well at least i thought they were happy. one of my mice her name is pip. i discovered a red spot type thing a size of a pea on the back of her neck and she,se losing her hair around her neck to, plus to make things worse she has lump on her back end as well but shes eating and drinking running about and going to the toilet just fine.i don't think it's bugging her but the lump sure is bugging me.i'm scared to because I've only had her for few months along with gizmo the other female mouse shes fine a bit over weight but i got that sorted out and shes happy now it's just pip I'm worried about her and what i can or could do to help her..

Answer
Hi Becker,

There are several things that could be causing the spot and the lump, and it would definitely be best if you could see a vet and get their professional opinion and help.

As far as the spot goes - is it in the shape of a ring, or just a round spot?  Is it raised at all, or scabbed?  Could it be the result of scratching or is it confined, more like a bug bite?  I really need more information to help out, but a vet visit would be even better and would save the both of you a little time.

Mice can get ringworm (which is transferable to you, too), which would be in the shape of a ring and would need antifungal medication to be treated.  If it looks like it could be a result of scratching (not perfectly circular, more like a blotchy spot with some scabbing) it could be irritation from something that's making her itchy.  This could be mites, allergies, or something else.  If it's a confined, clear red spot and the hair around it is just missing - it could be a bite from scuffling, a bug bite, or something else entirely.  As you can see, there are quite a few possibilities, and what's causing it will determine what treatment to use.  If you can't see a vet please feel free to send a followup question, and see if you can snap a picture of the spot and include it so I can get a better idea of what might be going on.

I need more information on the lump, as well - where exactly is it located and what does it look like?  How large is it, and what does it feel like?  Has she had any injuries in that area in the recent past?  Is there any fur missing in that area that might indicate scratching (which can sometimes cause an infection that swells), or are there any bites under the fur if you ruffle it?

Like I said, a vet would be the very best option if you can.  Not only can they help you figure out the issue in person, but they can provide treatments and medications that aren't always available over the counter.  If you can't, though, and I know sometimes it's just impossible, definitely write me back with a few more details and we'll see what we can do for her.  :)

Best of luck!
-Tam