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Mice/Small hard lump on mouse's back


QUESTION: When cleaning out my per mice I noticed that my long haired mouse has a small hard lump in the middle of her back.  It is pale pink in colour with a couple of darker spots on it, the lump is also quite rough. At first glance I thought it was a scratch, but definitely round.  It doesn't seem to be causing any discomfort.  I would be grateful for any advice.

Many thanks

ANSWER: Hi Danielle,

Is there any way you could send me a photo of the lump in a followup question, please?  That way I can get an idea of size, color, and texture a bit better than trying to imagine it.  Lumps and bumps could be anything from pimples to pests, bug bites, injuries, abscesses, tumors, or even allergies.  I will be able to give you a better guess after seeing it, but a vet would be able to diagnose it virtually immediately if that is a possibility for you.


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Spot on mouse
Spot on mouse  

I have finally managed to take a photo of the hard spot/lump please see attached image.

Thank you for all your help



It looks like her bump could be a growth such as a pimple or small abscess (like from a scratch), or even a bug bite.  Mice do occasionally get skin problems such as these, and if it is a normal occurrence and not related to a bigger problem like fighting, it will likely go away on its own.

I would suggest monitoring this to see if it decreases over the next couple of weeks or if it grows, but as long as it is not bothering her, I would not worry too much.  If it starts to grow, lose hair around it, become itchy, begins to discharge or the skin breaks, or if you see other bumps appear, I would visit a vet to see if they can identify the exact cause.  Like I mentioned before, only a vet can diagnose what it is, but the good news is that it doesn't look urgent to me!

Best of luck, and let me know if there is anything else I can do to help,


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