Mystery feather destruction/infection?

[Yardfulla poopers]

I apologize in advance, I don't know much about the birds, but my sister in law asked me why all her hens stopped laying. I suggested it may be mites/lice and explained how to best check for them. A week later, she sent me this photo and I was blown away! Any thoughts on what might be going on?
I have dealt with external and internal parasites in my flock but never seen anything like this. Any help would be appreciated.

 

[Eggcessive]

Is this the only hen who looks like this? Have they all molted this year? I would be concerned that this is feather picking or cannibalism. It can occur with over crowding, feeding less that a balanced 16-20% protein chicken feed, boredom from not getting outside to free range, too much light in the coop, and some more aggressive breeds or too many roosters.

Stress can lead to poor laying. Of course if any are molting, that would also make them stop laying. The fewer hours of daylight can also lead to the hens taking a break from laying over winter.

Here is some reading about feather picking and cannibalism:
https://extension.psu.edu/poultry-cannibalism-prevention-and-treatment

 

[Yardfulla poopers]

Thank you. She said there are two hens that look like this. I do know there are no roosters but there were several new additions to the flock last year.

 

[Yardfulla poopers]

They do have a run that could almost be considered free range but I will check with her to see how many are in the coop itself.

 

[Eggcessive]

If they have pictures of the coop and run, and some of the details from above, that might help. What are the breeds, how many chickens, and how much room in the coop?