I have a Domineque (Barred Rock)hen (4 months old) that I find lots(5 or 6) of feathers(some small, some wing sized) in her cage in the morning or evening. She seems to be always cleaning herself, could it be that? Also I use DE in the pen, no mites on legs, beak or butt. Other than that she is fine. Any ideas, or is it just a phase?