Reptile & Amphibian Forums

Ok, I know that nobody come on here these days, but on the off chance..... I started trying the feeder mice breeding to save a few bucks, but it isn't working out. I got my first batch of babies (pups?), from a group of three females and one male in a 50 gallon terrarium on the patio. after a few days the babies disappeared. next I removed the other two pregnant females to separate small 3-4 gallon terrariums in the laundry room; the first one to give birth ate her babies at about a week old, except for one which now has fur. the second female to bear, ate all her young at about 5 days old, and I found her dead in the water dish after returning home from the weekend. Out of about 36 total babies, I only managed to skim off about 8 to feed my kings and am left with only 2 female breeders and a lone fuzzy as of about an hour ago. Is this a normal mortality rate or am I doing something wrong? One more thing, early on, I didn't think I had a working male, so I bought another(which was smaller)and he lasted only about 3 days with the others, as they kept chasing and biting him till he died. My opinion of mice has hit a new low.

In my limited experience it's usually a result of stressed females. I worked at a pet store and had to manage about 40 breeding groups of mice, rats, and hamsters and it seemed first time females had a higher than average chance at eating babies (maybe stressed from being a new mom) and when we did very complete cleanings (cages, shelves, floors etc) sometimes there would be several mothers kill/eat some or all babies. I've heard but never tested or seen for myself that a lack of quality food can be the cause as well. Regardless of why, any adults that killed babies more than a couple times became food.

you mentioned a back porch and laundry room? what are temps like and are they high traffic areas where the mice could be stressed?

I'd keep trying... keep the adults in a calm low traffic place with comfortable temps. if the females eat another batch of babies, get some different adults.

I produce about 6 thousand mice a week. Heres the deal, first, water, miss a day, and they eat their young, miss a day, and they miss a cycle, of course, missing one day, doesn't always result it that, say 50% of the time. miss two days does.
Miss a day of food, impacts them, Three days and they eat their pinkies, and move on up. until they eat eachother.
Also, rats carry virus's that kill lab mice, Swiss, Ross River, etc. A friend of mine who is a rodent breeder in San Diego, had his mice tested and they carried five types of virus.
When they have this virus, they grow up fine, but die after the first litter, They waste away after giving birth. Brown mice, seem to not be effected by these virus.

They can and do reproduce in a wide range of temps, but I found that 75F or thereabouts is great. Common sense here. high fat diets allow for colder temps, low fat diets allow for higher temps. Mice are easy, but you cannot make mistakes or they die.

Stress and/or lack of water or nutrition is the cause for eating babies. When the environment is free of constant stress, and the mice do not lack for water or nutrition, then there will be no baby eating.

This is all from my own experience - and listening to others who produce mice with no issues.

Thanks guys, I don't know what causes stress in mice, but mine do not get bothered as I live alone on a large, quiet ranch. I do not see them for a couple days at a time, just to add mouse pellets and change the water. They are very dirty in their habits; constantly fouling their water cups with debris and excrement. I tried using covered deli cups with a hole in the top, big enough for their head to access the water, it helps, but they still get it dirty quickly. The terrariums really stink after a few days, and are time consuming to clean out and replace substrate, so I keep them outside and/or in the closed laundry room. It still stinks up the house. It gets cold out on the porch here in the hills of inland San Diego county; close to freezing lately, but the mice have an upside down shallow cardboard box inside the tank, which they have filled with the straw substrate making warm nests with tunnels. I am probably doing everything wrong....the pet shop sells mice and is reluctant to give me any information on rearing them.
I trapped several brown mice and have them in about a 20 gallon tank in the barn. Maybe they will do better than the white ones, but they probably have parasites that could be bad for my Kings.