American Fancy Rat & Mouse Association

This article is from the WSSF 2010 AFRMA Rat & Mouse Tales news-magazine.

Breeding & Stuff

Mother Mice Eat Babies?; Baby Rats Not Growing
Mother Mice Eat Babies?

Karen Baglini, facebook
Q I purposely bought 2 pregnant mice from Pet Supplies Plus and they both just gave birth! Alice has maybe 14 babies and so does Slink! There are at least 25 babies in there. I can’t count them because there are so many that are wriggling around and because they all sleep on top of each other that it’s difficult to see how many there are. I love hearing their little squeaks!

Also, I have touched the babies a little bit. Will the mother eat the babies since I did that?

A You should be OK but mice can be a bit sensitive about their babies if they don’t know you well. If you’ve only had them a short time, I would respectfully give the moms their space until the babies are a little older. Please keep in mind that 14 is more babies than mom can feed at one time and the numbers may decrease [a mouse can only nurse 10 at a time]. Female mice will frequently cut their litters down to a size that they can raise comfortably. Carol Lawton

Baby Rats Not Growing

Jade Porter, facebook
Q My rats have given birth. One litter is 12 days old with 9 babies and the other is 10 days with 13 babies. The first litter is doing very well, but the larger litter is very weak and frail, and they haven’t grown much since they were born. I’m feeding the mom good quality rodent blocks, treat drops, and ferret treats for protein, along with fruit and veggies, all daily. Anything I’m doing wrong, or not doing?

Answer from Amy, Camarattery
A I would recommend adding more protein. Make some hard boiled eggs, and even jarred baby food (meat). Also, increasing her intake of food will help. And to do this you can also mix some dry infant cereal. This will get her eating more and sending that along to the babies.

Answer from Karen Robbins
A You can also supplement with a good quality dry dog/puppy/cat food and Ensure or Boost or other equivalent liquid nutritional drink supplement (Walgreen’s has one).

It could be that there are just too many babies for the second mom to care for properly, she does not have enough milk, or something is wrong with them and they are not able to nurse properly. You could try putting a couple on the mom with only 9 babies that seems to be able to handle that many and see if the fosters put on any weight. Remember, a rat is only able to nurse 12 at a time, so in the litter of 13, one will always be left out during dinner time. If the babies are not able to get enough milk with each feeding or have something wrong with them, you will more than likely lose some. If the mom just doesn’t have enough milk for that many, the entire litter suffers.

You don’t say how old the moms are or if this is their first litters. Some very young rats who get accidentally bred at 2–3 months are just too young to try to raise that many kids since they are just a kid themselves and this will hurt the mom as well as the litter.

Read the following articles for more on caring for large litters and nutrient requirements of rats:

Updated February 18, 2014