arlee453 has a good point. Sounds like a deficiency of some sort.
One other (perhaps more remote) possibility is medication ~ I have read that some worming medications can cause feather abnormalities if administered during a molt. Have you wormed lately?
I have 40 chickens all eating layer food from TSC. They also graze in the yard and woods all day, and I'm sure are eating bugs, probably lizards.
Wouldn't they all look the same if it was a feed problem?
I have never wormed them, since they never seemed to be sick. I have also kept them away from other chickens and chicken owners (with one exception). They are exposed to wild animals, though.
Thank you for your help. Are there any other places I could look to find an answer? Before finding Backyard chickens I knew of a a site who helped with health issues, but now I can't remember what it was, nor find it searching.