one of my cornish rocks has mysteriously started favoring one leg. she is only 7 weeks old and her food is cut back to meal a day which she shares with two other cornish rocks so she is not over weight like the breed is prone too being a meat chicken. there is no apparent injury, and as far as i can tee no broken bones. she has been in a cage on the floor, so she hasn't fallen from anywhere. does anyone have any ideas? and if so susgestions on how to fix it. she is very pitiful and seems to be in a lot of pain, whatever it is. please help.