One of my 5 month old hens, which was normal until this morning, has started walking funny. The best way I can describe it is that when she.walks slow she doesn't extend her legs all the way and she is flat footed. Like when little kids squat down and walk. Then when she tries to go fast, she loses balance and rolls to the left. Any ideas? She hasn't started laying yet...could she be egg bound? I cant see any.injuries, and none .of the others are doing this.