Originally Answered: New Baby rat making weird noise is it normal?
Could be you've just got a very vocal baby, but it might also be that he's in pain - rats squeak when the pain is sudden and/or severe.
If the jerking motion happens a lot, I'd say he's got or is developing active myco. All rats outside of a lab have something called mycoplasma. http://ratguide.com/health/bacteria/myco... It's not communicable to humans. Not every rat gets sick from it, but most will eventually. How old is the baby?
Myco is activated by stress, drafts or a very dirty cage.
Active myco needs antibiotics, i.e. a vet. This is NOT negotiable! It will NOT go away on its own, and CANNOT be treated with anything over the counter. Only a vet can tell for sure whether he's got a respiratory infection. Go find a knowledgeable exotics vet - your average cat-and-dog vet won't have any idea what to do for a rat.
Is he a single rat? Rats REALLY don't do well on their own. Solitary rats get depressed, clingy, neurotic, and sometimes aggressive unless they get upwards of 14 hours a day of direct social contact with a person. Lone rats also get sick a lot easier than those that are kept with other rats.This is why rats should ALWAYS be kept in same-gender pairs or groups. Not very many people can provide over 14 hours of attention EVERY DAY. Please read up on quarantine and intros in the following links:
http://ratguide.com/health/basics/quaran... - this MUST take place at a friend or relative's house for a MONTH!
Basically, take the rat to the vet, and get him a buddy or two if he doesn't already have one.
Edited: To Missy: Oh really? Tell that to the people (some of them rat experts) on this board: http://www.goosemoose.com/component/option,com_smf/Itemid,118/forum,rat
Do your homework. Just because ONE rat DIDN'T get depressed and two non-solitary rats got bitey doesn't mean that all rats are perfectly fine on their own for 2 to 3 years with sphoradic human contact. Your girls might have been the result of a backyard breeder throwing two bitey adults in the same cage to breed.
Rats are social, just like people. Imagine being in solitary confinement for 60 to 90 years with only one friend who only visits for a couple of hours, and not even every day. You'd go mental in short order - the same is true of most rats.