Q&A for How to Breed Mice

Yes, most likely all three of them will get pregnant.

Generally, yes, a line of mice is usually not at risk for defects due inbreeding until 25 generations (a lot of pet store mice are inbred). After that, fertility will be an issue.

If you're absolutely certain that you have a male, he may be sterile. You might have to replace him with a different male if you want to breed.

If a female mouse is pregnant, you will notice signs such as nest building, eating more than usual, and an enlargement of the stomach area.

3 - 4 weeks on average.

Never put two male mice in with two females, only put one in with them. This is because the males will most likely fight.

I believe so, yes. Female mice are very motherly and community driven, and aren't very aggressive to begin with.

You won't necessarily know, so just keep trying. They are fighting because the female most likely isn't in heat, or she just doesn't like the male.

If the litter is with the mother only, they can be weaned after 21 or 28 days. If the litter is kept with both parents, weaning should be done after 21 days.

It depends on the parents genotypes. Supposing the male has two black alleles (BB) and the female has two brown alleles (bb), then yes, the entire litter will be black and their genotype will be Bb. The lowercase "b" is the brown allele, and this means that the entire litter will carry the brown gene (meaning they can pass it on to their offspring and have brown offspring), but will have black fur themselves. However, if the dad was a carrier of the brown gene, meaning that his genotype was Bb, then the litter would have a 50% chance of being either black or brown, because they could be either Bb or bb. I suggest looking up Punnett squares on Google and drawing one out.

They are two completely different species, so they almost certainly would never breed. In the wild, rats actually hunt and eat mice.

I have seen a maximum of 13 babies at once.

You should try looking this up on Google. Most often, you can get mice at a standard pet store. If not, your local aquarium stores might offer feeder mice for snakes or fish, which you can instead buy as pets.

No, because the male will likely get all of the females pregnant.

No, it is not recommended due to serious health risks.

Yes. The color doesn't matter. Unless the mouse doesn't look healthy, you can breed it.

You should look into getting a small light or heating pad on low heat.

Yes they will, especially if their nest/sense of privacy and safety is disturbed. I have a large aquarium that I cleaned without knowing there were pinkies in there. It was horrible to see them killed and eaten by the adult mice, which only happened because I disturbed them.

Don't start from baby mice. Get a pair of mice of the opposite sex, or a male mouse with two or more female mice. Once the female mice are gravid, separate them from the others and keep them in a cage or a tank with new bedding and hide. Then all you have to do is regularly feed and water them until the pups start roaming around on their own. Reptile keepers are the main target. Snake owners are the primary and potential buyers to buy your mice to feed their pythons or whatever snakes they have.

Usually once will be fine, but it's dependent on the individual mice.

You should always have one male and 2-4 females. Not too many, or they will take over.

Yes, but they will be lonely because they are usually supposed to be kept in pairs.

Sometimes a mother mouse will eat the babies if food is scarce or if they are unhealthy. It's a part of nature but if you don't want to lose even the unhealthy ones you can try to take some of them and separate them. You will have to feed them by hand but that's the most common way.

He will be aggressive with the other male, but he shouldn't be aggressive towards the female.

There will be a “plug” visible on the rear of the female. This plug is actually hardened semen, and it should remain in place for about 12 hours after mating.

There are no ways of telling which genetic traits are dominant or recessive, you have to wait and see. All patterns on a fox-coated mouse are very different and unique.

Mice gestate for a period of 21 days, from date of conception. A vaginal plug will be present at day one of gestation, but will quickly fall off.

The babies' eyes will open fully in about two weeks after birth.

Yes. The mothers will not be finished nursing until they have all of their fur.

Refrain from cleaning, if at all possible. The mother will do a lot of the work. Spot clean if necessary. If you touch the pups, the mother may disown them due to human scent.