Rats at war

Question
hi i have a question.I have 2 female rats.I have a large cage and all but the one was born feb 10,09 (its now 3/20/09)and the other is about 5 months old.My little one come from a what i thought was a good breeder but it now looks like she is pregnant.My older female every time i try to put them together she bits or pins the smaller one down..Any ideas on what i can do..Please reply to my address of  as i don't get on this site much..thanks for any and all help i can get..I love my rats and want them to get along

Answer
I'm sorry for the delay responding, I've been sick with the flu.

If your little one is in fact pregnant, you need to separate her in order to keep her and the litter safe. When did you first suspect she was pregnant, and how long ago? Rat gestation is 22 days. If you got her more than 22 days ago, and she still hasn't had babies, she may not be pregnant.

Is the older rat drawing blood when she bugs the baby? Normal rat behavior for introductions usually includes some screeching/chattering, puffy coat and war dances, chasing each other around and flipping each other over. If she isn't blatantly hurting the baby, just let them work it out. Every time you remove the younger rat and put her back in, it enforces that dominant behavior in the older rat and starts the whole cycle over again.

If she is really truly trying to hurt the baby, though; you need to stop and go back to "proper" introductions; introducing them in a neutral, scent-free area and having their whole cage sanitized and cleaned. Some vanilla (real vanilla) extract behind their ears and the base of their tails may help some, also.