One of my hybrid hens will not bear weight on one of her feet! She's between 6 months and a year. Her foot looks fine, but she holds it up and will not let it touch the ground most of the time, and when she does, it bears little to no weight. This has been happening for a week now. She is free ranged on my 8 acres with 27 other chickens... She gets around alright, but not as well as she could, and Im worried she's in pain. what do you think could be wrong?