Does anyone have any ideas on what might be causing this? They are 6 six weeks old and they are with 100 other chickens (st run)including Rhode Island Reds, Black Australorps, Shavers, and White Rocks. I noticed about 5 of them (3 Reds, 1 Black Australorps, and 1 shaver (barred cross)) are having this problem. My Son noticed one of the white rocks with a feather in it's mouth, but we have not witnessed any pecking. Is this a diease problem or a pecking problem? What's the Solution? Thanks!