Mice/Mice: strange behavior, tumor.
I have two mice that been with me for about a year, maybe a little less. One of them I bought was sort of a 'chunky' mouse. The black one who I've had longer is very small and skittish. The 'chunky' one was getting along with her but then about four days ago I noticed she was skinnier, the tumor that I mistook for 'fat' was gone but I can feel her little bones now. She was fine but last night I noticed she's literally throwing herself against the cage walls as she walks, I saw her drink water but today, nothing at all. Her head moves quite a lot, like she can't really lift her head and it causes her to fall over. I sort of realize she's going but then today I realized the black mouse has a tumor on her backside that I clearly see sticking out. She still runs and plays but she's losing fur on her face. What I want to know is are they both dying? And is it likely a contagious disease between the two of them?
It isn't good news I have for you.
The first one very likely has a brain tumor. There is nothing to do but have her put to sleep. She is suffering. Until then please put a soft cloth on the sides of the cage so she can't hurt herself. If she can't eat or drink you must help her with a syringe every 4 hours or so. You can use Ensure or soy infant formula. The quicker you can get her to the vet to be put down, the better. Poor little thing.
The second one *could* have an abscess, but a tumor is very much more likely. If it basically occurred overnight, it might be an abscess and a vet can aspirate it (drain it) and give you antibiotics. You might have to care for the wound carefully for a while, cleaning it inside with saline twice a day. If it did appear overnight, and you can't get it to the vet, write back and I will help you to try to treat at home.
But most lumps on mice are tumors, and mouse tumors are generally malignant-- cancer. You take them off, they come back. In that case you watch the mouse carefully-- and wait till its quality of life is compromised and then put it to sleep. Basically you ask the mouse (use your inagination) every day if it is happy to be alive today. That answer determines the time. The tumor will be getting larger but the mouse does not care how it looks.
The hair loss is separate. That is most likely mites. She should have a drop of cat/kitten/puppy (not dog) Revolution on the skin on the back of the neck, after which she must not wash for ten minutes. You can get this from the vet.
You might choose to have them both put down at the same time. It is only shortening the second mouse's life by a bit.
I am so sorry about the mice. If you get more mice, you will need to sanitize everything washable in hot water with a little bleach, and throw away anything not washable.