Reptile & Amphibian Forums

I recently started my own rat breeding setup with auto water system and all and was wondering how to tell if females are pregnant i know they all have been mating and a couple females are getting big bellys and there nips are showing a little but is there more to know.I got tired of paying 4.99 for a small rat at local pet store and 2.50 for small mouse.
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spider m
pastel f
graziani pastel m
high c albino m
het for albino m
het for albino f
cini f
orange ghost f
mojave m
rodent breeding setup
and still growing

All the signs sound good. When they're close YOU'LL KNOW!!! They will look like they're about to blow up!!

As previously stated, it looks like you are seeing all the signs. In my experience, the females will look like they are about to explode, but it will still be another 3-5 days before they give birth. Make sure they are getting adequate protein in those last 3-5 days and it will really pay off.
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Lincoln, NE
0.1 Pastel, 1.0 Pastel het Pied, 0.1 Pied, 0.1 Cinn, 1.0 Black Pewter, 1.0 Woma (hidden gene?), 0.1 Yellowbelly
2.0 Normals, 1.0 Thayeri, 0.1 Thayeri X Alterna, 0.1 crazy cat, 1.0 husband

It takes about 21 days for a rat to have babies, and if she's noticeably getting bigger leading up to 21 days since the last time you noticed mating, then you definitely have pregnant rats.

Mice have a slightly shorter gestation period, 19-21 days is the usual range.

Another way to know your rats are pregnant is if all breeding stops. A rat's cycle is once every 5 days and they go into cycle (or heat if you will) within 24 hours of given birth as well. So if you stop seeing any signs of mating after 5 days since the last sign of mating then you know she's pregnant.

Mice I think have a slightly shorter cycle, I think its 3-4 days but not 100% sure on this part.

Keep in mind though that if environmental conditions aren't right for rearing babies, both mice and rats can put a 'pause' on their pregnancy till conditions are ideal. Thus if food quality is poor or insufficient or temperatures are not right you will notice no babies will come. Overcrowding and stress will cause this too and mice who do have babies anyway, tend to eat them up if conditions aren't right.

A new colony of rats can take up to 3 months before they have their first litter even with animals who are at the best age to start breeding when they are all put together. They seem to need this settling in period before babies start appearing.
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PHLdyPayne

Also with my experience with mice. I am not sure about rats but separate the females that are pregnant to two per cage that works better so less chance of them being eaten. I males will eat the babies because they get all the attention also if you have to many pregnant females the other females with eat the babies a day or two before they give birth.