This is NOT a feed issue. I’ll tell you exactly what’s happened. Your hen is growing her permanent feathers. I’ve circled the area and pointed to a couple of them.
At this stage they are known as “Blood Feathers” because when feathers grown in for the first time they have a blood supply to grow and then become what you see in a regular feather- hollow and white.
Your other girls have figured out that if you pull a blood feather, you get a tasty bloody treat. Chickens LOVE blood. LOVE it. So, they probably figured this out by accident the first time in routine pecking order activity- and now your sweet little EE is a feast.
The “good” news is that they’ve pulled the feathers completely out as blood feathers, so they will likely grow back in completely.
Your nursing schedule is exactly right – vetricyn and maybe some antibiotic ointment on the bare skin. She will need to be kept separate until she’s done growing the permanent feathers. It will take a while, the best way is to build an adjacent pen of some size where they can see but not touch … and most importantly – predator proof!!!
The crate you have in there is good- but please please please put hardware cloth (same thing you’ve got your run done in, nice job!) over that crate – otherwise they will just reach right on in there and keep pulling her blood feathers- and do bring her in at night.
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