Why?

[Cryss]

No all girls

That's a surprise! Ok then I would look at environment. What is the square foot of the coop? Square foot of the run? How many birds?

 

[Julieanne303]

What are the coop dimensions? Do they free range during the day or do you have a run?

They are both. We only let them out when we are here

 

[micstrachan]

Oh wow, that skin is really irritated. Do you have a rooster and could she be over mated? She also looks pecked (bruising below vent). Finally, I would take a good look for external parasites.

 

[Matilda Belle]

I think as long as they have access to that run and aren't being held in the coop for long periods of time (that's a very small coop), there shouldn't be a pecking issue.

I would clean out the coop and run completely of bedding, replace with new bedding, and treat the chickens and coop/run with permethrin. I would also take any advice from @Eggcessive

 

[alexisrambles]

x2!

That red and irritated skin really looks like what my chickies had. The spray is really easy, and since your coop is mostly plastic, it should be easy to spray down with a hose and clean really really well!

 

[micstrachan]

Sorry... I got distracted while posting and a bunch of others posted before I got mine in. Glad you’re getting lots of help!

 

[Eggcessive]

Many people have good luck with the Nustock Cream. It is a sulfur-based product which is anti-fungal, anti-insect, and bad tasting. The pine tar works well too. Both products have healing properties, and taste bad if another pecks.

 

[Kathy Golla]

@Eggcessive I'd like to suggest this is depluming mites. Usually when just one bird looks like this, that can be the culprit. The dupluming of the feather shafts are telltale, as well as the timeframe (a year).
Signs of depluming mites would be the bird overgrooming, overbathing and chewing her feathers off. She has a lot of breakage.
@Julieanne303 , have you noticed this white bird overgrooming herself, overly taking dust baths, chewing her feathers off in the time she's been losing feathers?

 

[Kathy Golla]

That black hen's got something going on too...is that a specific breed that has no feathers on her head?

 

[Julieanne303]

@Eggcessive I'd like to suggest this is depluming mites. Usually when just one bird looks like this, that can be the culprit. The dupluming of the feather shafts are telltale, as well as the timeframe (a year).
Signs of depluming mites would be the bird overgrooming, overbathing and chewing her feathers off. She has a lot of breakage.
@Julieanne303 , have you noticed this white bird overgrooming herself, overly taking dust baths, chewing her feathers off in the time she's been losing feathers?

No not at all. Nancy the little white one constantly cleans. But the other two do not
We have treated for red mite and worms. We took the coop apart and jet washed and disinfect it. No sign at all oh anything. And we looked very very close in every nook and cranny