how soon is too soon to take baby ratties away from mommy?

Question
Well 5 days ago I got two baby rats from a friend of a friend of mine. My friend had gotten some from the previous litter at 2 weeks of age, and the rats are healthy and very happy! and I also got my two girls at between 2 and 3 weeks of age. They are both eating well, and seem very happy and healthy. But I am hearing now that they shouldn't be taken away from the mommy till between 5 and 6 weeks. Does it really matter?
is there anything I can do to ensure they will be healthy and happy even with out being with their mother for the required time?

thank you very much!

Answer
Yes, it matters a LOT. It's the equivalent to weaning a 4 month old human baby directly onto table food. Their jaws and teeth, and their coordination, aren't quite strong enough to progress to solid foods, their stomachs aren't yet used to it and it could cause some intestinal distress. At 2 weeks old babies are still nursing off mom and learning to be a rat. Even in the wild, babies don't wean until at LEAST 4 weeks; and that's pushing it. Respectable breeders won't wean until between 5 and 6 weeks; when babies are 100% self-sufficient and no longer nursing.

Babies separated too early fail to really learn a lot of the basics behind getting to know life with another rat.. they also lack the nutrition that comes with nursing for those extra three weeks; Mom's good immunities to illnesses they may encounter in their environment and the extra iron and other good vitamins.

Ideally, you need to get some KMR ["Kitten Milk Replacer"] and offer them that in a very shallow dish or off the end of a needle-less syringe to substitute. You may need to soften their food by soaking it until they can get the hang of chewing.

And please, please, please educate the place you're getting them from!