How do you take care of a small mouse?

Question
I found a small mouse on the street and we are keeping it in a cage, but how do we take care of it? It is a white mouse with red eyes and a pink nose what kind is it and how do you recommend we take care of it?

Answer
Hi,
thank you for your question.
You found a fancy mouse that either escaped or was abandoned by someone. To take proper care of it, you will need a cage,  a tank or you can build an enclosure yourself from OSB panels (can be bought at hardware stores), here are pictures of good mouse cages:
http://www.diebrain.de/ma-gehege.html
The cage should be at least 30x15x15 inches long, wide and high.
The mouse should have a house, climbing toys, like ladders, ropes and branches (hazel, oak, beech, birch, willow, apple, pear and poplar are safe as long as you are sure the trees haven't been treated with pesticides and as long as the don't grow next to a busy street). Cardboard boxes, egg containers and toilet paper rolls make good hiding places and chewing toys. If you want to offer a wheel, I can recommend the Wodent Wheel:
http://www.transoniq.com/
Most other wheels are way too small and some are outright dangerous, the mouse can pinch its tail between the wheel and the spokes.

For food, offer a mixture of bird seeds, like Kaytee Fiesta for Parakeets  (which has many different small seeds), mixed 2:1 with cereals. You can buy mixtures of five or six different cereals at health food stores, they should contain at least wheat, barley and oats.
For fresh food, offer carrots, cucumber, dandelion (roots, leaves and flowers), daisies, marigold, kale (mangold), parsley, beetroots, celery (stalks and root), apple, strawberries, zucchini, spinach, chickweed, ribwort, fennel, corn and pumpkin. Fresh food should be offered at least every other day.
The mouse will also need animal protein: mealworms, crickets/locusts (dead or live), silkworms or dried brine shrimp. This should also be offered ever other day. Water must be offered all the time.

For bedding, you can use wood shavings (not pine or any other resinous wood), hemp or flax bedding (ofteh used for horses). Unscented toilet paper makes good material for nest building.

If the mouse is a female, it will need a friend, another female. Introduce them on neutral ground, for example in the bathtub. If they get along there after a few hours, put them in a small cage or kritter keeper. After a night spend there, they can move into their normal cage again, but it should be cleaned with hot water and vinegar to get rid of the smell and mustn't contain anything but bedding, some hay, food and water. If the mice continue to get along, you can start putting in furniture and toys, one item per day.

Here are pictures of a female:
http://www.diebrain.de/pix/ma/Weibchen.jpg
and male
http://www.diebrain.de/pix/ma/Bock.jpg
mouse to help with sexing it. Older male mice have huge testicles. They don't get along with other male mouse, so unless you can find a vet to neuter it, it will have to live alone. A neutered male mouse can live with females after three weeks.
I recommend a vet visit to make sure the mouse didn't pick any disease while running around outside, mice are very suspectible to respiratory infections. You can find a list of rodent vets here:
www.rmca.org/Vets

I hope I was of some help to you
Jennifer