New biting problem

Question
QUESTION: I've had Courage for several months and have never had any problems with her. However, these past two weeks she's bitten me three times, the last one being very deep. I haven't changed anything I've been doing, and two of the three times she bit me I was petting her. Please help! I don't want to keep her caged all the time but I REALLY don't want to get bit again.

ANSWER: What was the situation when you were bitten?  Could it have been that you were petting her while she was sleeping or tired?  Some rats do not wish to be disturbed during their quiet hours, usually during the day.  

However, if you have previously petted her during sleeptime without any attempts at aggression from her, it is quite possible that she is ill or under some kind of stress.  Is she showing any subtle signs of illness, like lethargy or poor appetite?  Is she acting as before during her free play times, with lots of energy and curiosity?  If you notice any other behavior changes aside from the biting that suggest she is ill, I suggest you take her to your vet for an exam.

Good luck with Courage and please let me know if I can help you with anything else.

---------- FOLLOW-UP ----------

QUESTION: That's the thing. Her appetite is swell. There are no other behavioral changes. And when she bit me, it was during play time. I let my two ratties out to roam on my bed, and she came right up to me, so I pet her. This is true for both times she bit me (there was a third time, but I know what happened there).

Answer
Okay, let's try to figure this one out.  I currently have one female "biter" as well.  Mine bites when she's bothered at sleeptime, hard but never breaking skin.  She will always bite me on places on my face for some strange reason (nose, lip, etc) if I put my face close to her, again hard but not breaking skin.  During nightime when she free plays or when I pet her, she never bites my hands or any other parts of my body but will sometimes stop and groom me, quite hard with her teeth but it's not painful.  I attribute all of this to her personality.  She was always the most of aggressive of my females, the dominant one, who would make the others squeak when she groomed them.

Having heard this, do you see any similarities?  Is your girl the dominant one of yours?  During next playtimes, try not to pet her or put your hands or face anywhere near her.  Just sit with them and interact without your hands.  Let her climb on you if she will.  Let me know if she bites you anywhere else?  Moniter her behavior closely so if she does bite, you can recall her actions right before biting.  Was she overly hyper playing with her "sister" right before?  Does she ever bite her sister and make her squeak?  How hard are these bites, breaking skin or not?  Are you certain she is not just trying to groom you (some rats are very aggressive groomers)?

Please get back to me.  I'd like to help you figure this out.  I have friends and rat mentors that I can also confer with for their ideas.

PS - you may wish to wear thick gloves during playtime if you feel your hands are her target.