Molt, mites, or..?

[Glory to His name]

4 of 21 birds in my flock (each ≈1 year old) are missing feathers at the base of their tail and otherwise looking ragged. Some of the feathers almost look cut? Thinned?

They were originally eating Kalmbach layer. Thinking they were possibly picking/eating each others feathers, two months ago I switched to a higher protein all-flock and started providing oyster shell in hopes that would help. I haven’t noticed a difference.

I’ve checked everyone thoroughly (not just the rough looking gals) and haven’t seen any signs of mites.

I’ve never experienced molting with my older hens.. is that what this is? If so, is it normal for it to go on so long? It’s been almost three months now of them looking like this - hasn’t gotten worse necessarily but also hasn’t gotten better. (We do have a rooster - he seems gentle enough when he mounts the hens, but regardless, this issue came about before he even hatched out of the egg.)

This is the worst looking one.. and the rooster doesn’t even bother trying with her.

 

[Wyorp Rock]

Feather loss pattern looks consistent with breakage from mounting/mating. The broken feathers will be replaced once she molts.

You may have a hen that is mounting her, watch to see if that's happening.

 

[ChickyMudder]

Looks like my feather eaters. I’m doing a process of elimination. I wormed them. I treated for mites. Now I suspect feather eaters. I’m also feeing protien supplement and no change …
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