Q: I was in the pet store four days ago and saw a little pinkie mouse with no adult mice with it. I thought it was dead. Anyway, long story short, I have it now and am looking for tips on how to keep it alive. I have several adult mice and have rescued many little fuzzy mice with great success in raising them. I am feeding it formula and rubbing its stomach to help it go potty. Is there anything else that I should be doing or that would increase the chances of it surviving?
A: Unfortunately it is very common for female mice to become pregnant and deliver their litter in the tanks or cages at a pet store. A mother mouse is occasionally sold without pet store staff realizing that she’s raising a litter. Female mice can also become seriously stressed by their environment and simply abandon their babies. You did a very kind thing for this baby mouse, but I would never recommend that someone inexperienced in raising pinkie mice take on this task.
It sounds like you’re doing all of the right things — keeping him warm, feeding small amounts every hour or two, helping him potty and keeping him clean. Without his mom, that’s really all that can be done. Even if you had a nursing female mouse, she would very likely reject the tiny baby and would probably kill him. She’s not being cruel; she’s simply protecting her own babies.
I have heard of female rats nursing baby mice but the best chance of success is with a mom that has a small litter (four to six babies) of newborns. With a bigger litter, the baby mouse wouldn’t be able to compete for food against the much larger baby rats. While female rats are known for their strong mothering instincts and will try to nurse almost anything, there is still a risk that she would reject or injure the tiny baby mouse.
Unless an acceptable rodent mom is found, just keep doing what you’re doing; it’s worked for you in the past, and there’s a chance that your experience and care will pay off with this one. I wish you the very best in all of your efforts.