wild baby mouse

Question
My cats "found" a baby mouse, which I took away from them. It was unharmed, but is VERY young. I have him in an aerated box in my bathroom, w/ TP for softness. I gave him a piece of cat food (dry) which he licked but couldn't eat. I mashed several up in warm milk, but he didn't seem to be able to eat...so I tried to feed him warm milk, which if I put in my hand he does "accidentally" get in his face, but he seems much more interested in climbing into my hands and feeling the warmth. He makes little chuffing noises, whcih I assume are  attempts to suck. He HATES to be put back in the box, preferring my hands. I know that I need to get some fluids w/ nutritious value into him or he won't live. Can you help us?

Answer
Hi Nancy,

Caring for young mice is very difficult no matter where they came from, unfortunately.  The sound he's making may indicate a health problem, in which case there may be nothing you can do.  You've got a good start with the box, however.

The first thing I'd do would be to check out this link:  http://www.rmca.org/Articles/orphans.htm  This is for mice, not just rats, and gives a very thorough guide on where to start with feeding, how much to give, and how to prepare it.  It's something I still refer to.  Cow's milk isn't easily digestible for infant mice and can cause diarrhea and tummy bloating, so if you happen to have a general store that sells pet supplies I would try to find kitten or puppy milk.  A syringe (without the needle of course) can be very useful in making it easier to feed, but be careful not to force any into the mouth quickly and cause the pup to aspirate.  Figuring out age can also be very useful - does the mouse have hair?  Are its eyes open?  Generally the coat starts to come in around a week or so, and the eyes typically open by the second week of age.  Once the eyes are open there's not usually a need to help the mouse go to the bathroom, but before then it's what starts the digestive system and initiates the appetite, so it's very important to use a warm cotton swab or tissue to massage the genitals before feeding.

Older mice may have strong preferences about which position they are fed in, so try holding it differently until it starts to accept food.  Older mice with their eyes open can be offered solid foods to explore at their leisure, but if he is behaving lethargic or still very young you may not have much luck convincing him to try new foods.  When they are still very young, mice need fed every couple of hours.  A healthy pup will let you know by stirring and becoming restless or even making tiny noises.  After feedings are generally naptime, and since they have trouble until they are older maintaining body temperature, you should place a heating pad beneath the box on its absolute lowest "warm" setting (the bottom of the box should only be slightly and consistently warmed, never hot!).

The most important things are to feed consistently with a warm (not hot) milk that has no lactose in it, keep the box warmed around the clock, and help it eliminate.  I really need to stress again that this is not easy at all, and sometimes even when everything is done right they may not make it.  It's unusual for a young mouse to be out from the nest, so it may be that mom kicked it out if there was something wrong with its health.  You can get a good guess at its age using this chart if it helps:  http://jaxmice.jax.org/literature/factsheet/LT0001_Pups.pdf

I hope he's still hanging in there, and best of luck!  Please write back if you have any additional questions.  It might help in the morning to go by a local vet or shelter and ask for help and advice - they will be able to show you how to feed and get a good meal in the little guy, or may even know someone locally who works with mice and can take over for you.  Good luck!

-Tam