Solitary Mouse Mutilating Himself

Why would a mouse cause wounds to himself and fur loss?

If a mouse begins to lose fur and have skin sores, ectoparasites might be to blame, but so might allergens, contact irritation, skin infections or cancer. Etouale/Pixabay

By Karen Rosenthal, DVM, MS


I have a pet mouse and out of nowhere he has big spots of fur loss and big wounds over half of his body. I don’t know why. He is the only mouse, but it looks like he is eating himself. He has lots of food and clean water. I clean out his cage once a week with water. I use newspaper as bedding for him. He is 1 year old I’ve had him since he was a pinky because my first mouse was pregnant. I’m having a hard time finding a mouse veterinarian in my city, which makes me sad because I know he has to be in pain. What can I do to help him?


I sympathize with you in that it is difficult to find a veterinarian who understands mouse diseases and is willing to see your pet mouse. My suggestion is that you find a veterinarian who is open to working with consultants either by phone or online, who can help solve your mouse’s issues by working in conjunction with your local veterinarian.

What you describe is very typical for ectoparasites in mice. Biting mites or lice can be very itchy and irritating to the skin. As the mouse scratches and bites at the irritation, large amounts of hair can fall out and the skin has excoriations and wounds.

Your veterinarian, even though he or she is not well-versed in rabbit medicine, should be able to do an examination looking for these parasites. Usually, they are not difficult to find. Treatment, under the direction of a mouse-knowledgeable veterinarian, can eliminate the parasites and also provide relief to the irritation. In some cases, antibiotics are necessary because a secondary skin infection has also occurred.

Even though your mouse lives by himself and his environment sounds great, these parasites have always been on your mouse and for reasons we may not understand, now they are causing problems for your mouse.

Of course, ectoparasites are just one possible cause of what you describe and that is why you need to visit a veterinarian who will work with a distant expert to help your mouse. Other causes can be allergens, contact irritation, primary skin infections and even cancer. As you can see, the sooner you are able to find a veterinarian in your area who will work with a distant expert, the sooner you can get some relief for your pet mouse.

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Article Categories:
Critters · Mice and Rats