• First, there are some foods you should never feed a mouse. The following foods are either toxic to mice, or are known to cause adverse reactions (such as itching, diarrhea, mental problems, etc):

• Chocolate
• Peanuts
• Acidic Fruits (oranges, lemons, etc)
• Acidic Vegetables (onions, garlic, etc)
• Raw meats
• Food designed for other small mammals

Mice are pretty tolerant of a wide range of foods. If you stay away from the ones on this short list, your mice should stay healthy and happy.

• What if my mouse is too skinny? This situation almost never happens as long as you provide your mice with adequate food. Mice are naturally slender atheletes, so don't think your mouse should be a big belly. Mice don’t require very much food to live so maintaining a surplus in their dish should be quite easy. If your mouse is not eating and looks sickly or lethargic, it is likely due to a medical problem. An inspection by a veterinarian should yield the problem. This also happens occasionally when you make a drastic change to a mouse’s diet. Whenever adding or removing something from your mouse’s diet, do so slowly. Add or remove a little bit each day until you’ve fully introduced or removed the food item in question. Doing this too quickly can confuse your mouse and leave it disinterested in its new type of food.

• What if my mouse is too fat? Obesity is a much more common problem in mice than undernourishment. If left up to them, most mice eat just enough food to remain healthy and not over eat, however, some mice are greedier than others and will gobble up all the food they can. There are certain breeds of mice that tend to be more gluttonous than others. Just like in people, obesity shortens life spans and increases risk of disease in mice. The best thing to do is get your mouse on a diet! You want to stop feeding your mouse fatty seeds and nuts and stick more to grains and fruits. Try to make sure they are getting all the vitamins they need. Once your mouse is back to a healthy weight, you can reintroduce the fatty seeds, but only in small portions. You don’t want your mouse blowing back up like a balloon.

• Some mice develop itchy skin rashes due to food allergies (also known as food intolerances. Corn and peanuts are likely causes of these allergies in mice. If you notice itchy, red spots on your mousse neck and head, this may be the cause. They may also have fleas or other ectoparasites, so its important to get your mouse checked by a vet if his symptoms don’t improve after changing his diet. To rule out food allergies, feed your mouse only simple grains (like oats and barley or bread) for about 10 days. If his symptoms subside, then slowly introduce his favorite foods back into the mix until you have found the offender.

• Continue to the next section: Mouse food and treats...