Quote Originally Posted by Byte
when reasearching we read that we should keep them apart untill the female is in heat (which occurs ever 5-6 days) then put them together so we dont stress the female out.

Is that just someones opinion or is it true?
I'm just going by the many threads I've read on the topic here....

Rats are social creatures and really need a buddy with them to thrive. But leaving a male/female together all the time can cause complications with the male trying to breed while the female is still nursing her current litter, etc. But until she actually gets pregnant, I don't see any reason to keep them separate.