Home: Breeding

Caring for the babies

Checking The Babies
Baby mice have very translucent skin; practically transparent. You will be able to see the cracks between the plates of their skulls, their stomachs when they are full of milk, the veins on their toes and all sorts of things. The milk is a good thing to watch out for. Since there is very little we breeders can do to make sure everything is going ok, aside from giving the right food and letting mum do her thing, it is nice to be able to check up on them and see that they've been eating. Don't worry if you can't see it, mice have a pretty fast metabolism and they probably just haven't eaten for a while. Check back in an hour or so, after the mum has had a chance to feed them. Often very large and very small litters will 'fail to thrive' due to, respectively, a lack of milk to go around and not enough stimulation to keep the female lactating plentifully. This is ok; they may just wean later and be runts.

Above: Runt (Ruby) and sibling at exactly the same ages: note the huge difference in size and development

You can see here how runts look less developed than 'normal' pups and they are also usually behind in achieving developmental stages, including pigmentation and opening their eyes. Both pups above are 3 days old. The pup on the right is a lot bigger and no longer looks like a newborn, unlike the runt.

Diet For Baby Mice
Young mice will need a high protein diet including sunflower seeds, dog biscuits, puppy/kitten kibble and lots of millet. Give them an endless supply of food - you will be surprised how much a growing pup can eat. A constant supply of water and/or water with added vitamins is essential and will also be consumed at a rate of knots. When the pups reach four weeks they can be given bread and fresh vegetables in moderation as with adults.

Once your young mice are separated and they are on solid food, they are ready to go to their new homes. Remember that mice are much happier when in groups so if you have someone who wants to purchase a mouse from you be sure that they will be in a group. Also keep in mind that male mice are better introduced while young or when in the same litter.

Group of three and a half week old babies

At about four weeks of age the babies are ready to be weaned from their mother. You will need to sex each baby and separate the males from the females. You can compare their genitals; boys will have a larger distance between the anus and genitals. Keep in mind the number you counted when they were first born of how many had nipples. That will come in handy. Have two cages (one for boys and one for girls). It is important to check every day for any sudden genital changes. The males' testicles will soon drop and it will be a definite way to sex them, although it is best to already have them separated before the testicles drop if this is after four weeks of age. It is also important to handle the babies as much as possible because this will help them become tame. The more they are handled the better.

Mum in the nest with her litter

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