Hi, I have 4 aged hens, all of good character (mostly) and we have a cat who likes to help feed the hens but runs off once the hens start stampeding towards him!
The hens don't have official names but some have a different ring or piece of coloured string around one leg, so green ring, green...
I have the very same thing happening with one of my hens! Did you get any answer and more importantly and ideas on how to treat? I thought it might have been something to do with mites so shook powder all over!