You are here:

Mice/lump on rescued mouse leg


hi i was walking my dog through my local woods and i saw like a hamster/mice cage i thourght id take a look to make sure and as i got to the cage all doors left open and it was full of water so i decide to double check and as i put my hand in there this little mice pooped his head out i couldn't leave it in the freezing cold with a cage full of water so i took it home went out bought new bedding food ect and the mice seemed fine its been 3 4 days now but the next morning after taking it home i notice it had a biggish lump on the inside of its leg it seemed to be moving around eating interested in new toys i put in there but i notice to day it seems the lump has got bigger ive never owned a mice before i had hamsters many years ago so im not sure whats going on with it im not sure if its male or female or if its even a mouse it looks like a mouse to me i notice when it climbed up on cage bars the lump has a red spot on it possibly a scab it seems to be fine but its really noticeable i have pictures of him/her if someone could let me know if is a mouse and what to do about the lump.

Hi Sabrina,

Omg the poor, poor little thing! May the mouse goddess rain smelly mouse poops upon the person who left this sweet little defenseless mouse! Thank you so much for rescuing it.

If it has soft lumps in back like a butt, it is a boy and those are its testicles. If not, it's a girl.

The lump on the leg could be a tumor, but since there is a scab, it is very likely an abscess, which is much better. A tumor would need an operation or just be left to grow, which is sad; an abscess is treatable. You do not mention how easy it is to handle the mouse, so I don't know if a vet could hold it still for an examination? It should go to the vet to have the abscess checked and lanced, and for the correct antibiotics.

If you can't get it to the vet - and I understand not necessarily wanting to pay a lot of money for a little guy you didn't plan on- then the only thing I can offer is a less effective antibiotic that you can get OTC for FISH. This certainly can help, but it isn't nearly as good a solution as a vet visit. Here are my instructions:

"Go to the FISH section of a pet store, or an aquarium store, and get tetracycline, sometimes called Fish Cycline.

"You are going to put some in her water bottle and try to get an initial dose inside her.  

"If you have the capsules, empty one capsule into a large water bottle or one half into a small one.  Shake extremely well.  If you have the powder,  1/4 flat teaspoon measure is the same as 1 capsule.  If you have the tablets, completely crush them into fine powder with the back of a spoon and use as powder.   This should be her only water source.  It's fine for any other mice to drink the water too, unless they are pregnant or nursing, so it is good that you have two separate cages. Cover the water bottle with tin foil,  because the medication is sensitive to light.  They may chew on the tin foil, because some mice love it. Don't worry about that. It's great for their teeth!  Clean the bottle and change the water every few days for 10-14 days.

"Next, take another capsule worth and mix it with one drop of water.  This will make a paste about the consistency of mustard.    You have plenty to play with, so if the mixture is too watery, try again.  Now pick up the mouse by the scruff of the neck.  This is the skin just behind her head.  This does not hurt her-- it's how her mama used to carry her-- but she will struggle valiantly.   Holding her gently but firmly,  quickly place a small amount, maybe 1/4 pea size, into her now open mouth.  This is hard.  Be careful of her nose!  Wipe a bit more onto her whiskers and chin.  She will ingest that when she washes herself.  If you couldn't get any inside her at all, wipe some more on her head and sides.  Put her back into her cage so she will wash herself.  Keep any other mouse from washing her, if necessary removing the other mouse for an hour.  

"Again, if you can get her to a vet at all, please do. The vet will probably give her Baytril and possibly also amoxicillin.  If you can get peanut butter flavored Baytril, she may lap it off of your finger; otherwise you are going to have to dose her twice a day for ten days. I actually recommend 14 days."

As for keeping the vet meds meds till next time, or continuing them longer, the amoxicillin must be thrown away after two weeks. The other two, if mixed, are good refrigerated for two months; if unmixed, good for a year. The tetracycline is good for whatever it says on the bottle, which is probably a few years.

Much luck to the little creature. I have a friend who found a rat like that-- in a cage by the side of the road in the snow. Unbelievable that he was alive. She named him Hobo. He was seriously skin and bones. Since then he is FIVE times the weight he was when found, a beautiful healthy boy. Maybe your mouse should be named Hobo too : ))




All Answers

Answers by Expert:

Ask Experts




I can answer questions about raising mice and caring for them as pets, with knowledge from my 38 years of having fancy mice as pets. I have NO MEDICAL TRAINING and you should take a sick mouse to the vet; but if you simply can't, I will try to help you. I LOVE PHOTOS!!! I ALSO LOVE UPDATES! Let me know how the little tyke is doing later on, for better or worse, especially orphans. It also helps me to help the next person. Please first search first: use 'Natasha Mice Mouse' with whatever else your question includes. Or check out these links: **** YOUR FIRST MOUSE (my video; rough draft): **** TEN VIDEOS ON RAISING ORPHANS: **** SEXING MICE: **** And some GREAT MOUSE INFO SITES:


I have had mice for 40 years (since I was 5!). I raised them when I was a child but now I keep all females, and never fewer than three so that if one dies the others are not devastated, because they have each other.

I run Rats and Mice are Awesome on Facebook. The official name is Rats are Awesome.

B.A., M.A., M.A. in Linguistics: Yale University and University of Connecticut

©2017 All rights reserved.