If her companion degu just died she would be extremely stressed, which could cause her to fur pull. When my degu's brother died he did this on his arms. It is more commonly on the arms, but it could easily be on the back legs too. Try to spend more time with her and possibly get her a new friend. Also after she is less stressed out you can get various creams and taste deterrents made for degus to prevent the habit from coming back. If you have any other degus check them for this as well as they would also be suffering from losing one of their friends.
Last edited by Wolft5; 05-15-2012 at 06:21 AM.