When to start intros?

[Leslie Marie]

I have a question. The babies are now 19 days old. When they are weaned, I want to move them in With Ash. That's if he get's a long with them. Otherwise they'll go in with my other three boys.  But I was wondering, when should I start doing intros? Should I start slowly introducing them now? Or should I wait until it's a little closer to 4 weeks?  Also.. when is it they should be seperated from Kali? It's 4 weeks.. right? Thanks. 

[squeaky]

Is Ash the dad? If not, I would wait until they are about 5 or 6 weeks old and away from mum. (they need separated between 4 and 5 weeks).
My experience is that a rat who knows or thinks he's the father will accept the babies, I guess they smell like part of his colony, but a rat that has had no contact with the mother may be aggressive towards them.
Once they are about 5  or 6 weeks old they seem to stop smelling like babies though and seem to be accepted either way as non-threatening juveniles.
(I read an article just recently that supports this, but I can't for the life of me remember where it was).
There are exceptions, but unless you know how your boy is going to behave I wouldn't risk it. They are far too small to defend themselves.

[Heather]

I had an adult male kill a 6 week old baby. I would wait until they're a few mos old and aren't so small. If you don't know already, baby bites are VERY soft so they have no way of fighting back if a big male happens to attack. Intro'ing females wouldn't be a problem but definately be careful with adult males and babies under 2 mos. I will never intro sooner than 2 mos, I waited until my 2 girls were 3 mos before intro'ing.

[squeaky]

Just want to add that I wouldn't necessarily move babies of 6 weeks in with the males, I was just meaning short intros under close supervision.
Babies here (UK) are rehomed around 6, 7 weeks old and our quarantine regulations are not nearly so strict. Many owners here just pop new babies in with their boys if initial introductions go okay though.
Good luck with them.