Reptile & Amphibian Forums

I tried looking through the old posts but didn't see any posts about this. What is the easiest/best way to sex a young rat? I have some young ones and I am kind of new to the breeding world.
If you have some time, I also would like to know what's the best set up for breeding. Two guys, one girl? Two girls one guy? I only have one snake and am trying to get practice for when I move out and get some more snakes. Thanks for any help.
She's about twice as big as in this pic now

Rats can be sexed just as mice, by the distance between the anus and urethra nub. For pinkies to fuzzies, you can compare the distance between these two points, the bigger the distance, the more 'male' the rat will be. When rats reach the fuzzy stage you can also see the nipples on the female. Once they are past 3-4 weeks of age, the male testies drop forming very obvious bulges, but again look for that greater space between the anus and urethra. (males can pull their testicles back into their bodies when nervous, though I don't see this happening in rats as much as I do with mice)

Rats can be kept in anything between 1:3 to 1:5 groups, depending on how large you want the containers to be. The more adult rats, you need a larger container to give room for the adults and all the babies. Overcrowding can result in litters being canabolized or no breeding at all.

Since you have only the once snake, I would recommend just a 1:2 or 1:3 group. The extra babies you can sell for a bit of momey to cover the cost of feeding and maintaining your colony or freeze them for later.