Quote Originally Posted by Deborah View Post
The average is 6 to 12 per litter (Can be more can be less)
The gestation is 21 to 23 days with the female being capable of being pregnant again within hours of giving birth.

So your total could be more but there are also other things you might take in consideration and that could lower your number if your breeders are house together at all time.

Communal breeding will lead to losses sometimes very little sometimes the entire litter

Back to back breeding will also take its toll on your females which could affect your production down the road.
I rotate my breeders to the freezer at 1yr. I currently have 25% of my racks dedicated as hold back racks so my breeders are constantly being replaced.

My understanding is that gestation is closer to 28 days. (just did a search and you are correct so that works in my favor)


Been breeding this cycle for about a year had a break because of an ant problem but before that it was 5 years. I have lost maybe a half dozen litters in that time frame.

Back to back breeding might take its toll, it is speculation. There is also speculation that the rest periods are just as hard as repeated breeding. Since a rat basically has 15 months of effective breeding life, wasting half of it on cool down periods is not logical for this application.

anyway....back on topic...

6-12...so you are saying average is 9...so not off much by saying 10.

I once housed my rats 1.3. I saw chew outs and fights. I increased to 1.4. No chew outs....fights are way less common. I increased my food hopper size and went to auto water systems. I have not seen a lost litter (from being eaten) since...

I specify about the lost litter because I have lost 2 females to what I believe was complications during birth (ie: still birth)


Considering I currently have 12 racks...2 rats isn't bad.

I figured I would ask for input because I was asked about output the other day and this was the equation I conveyed.