Chicken with missing feathers

[graceupongrace]

Hey everyone!
I have a chicken with feathers on it's rear. Hopefully you can see that I'm talking about. They are completely missing in some spots and thinned in others. Does anyone know what can cause this?
TIA!

 

[ChickenCanoe]

How old is she?

 

[graceupongrace]

She's about a year and a half.

 

[graceupongrace]

Some more info: She is one of 9 chickens in our flock. We have them in a fairly large run. None of the other chickens have this problem but some of them do have small bare patches on their backs from pecking .

 

[dawg53]

Is she going in molt? If so, you'd see feathers laying on the ground in the pen.
Have you observed any feather picking going on? That could be an issue and you'll have observe your other birds.
Also inspect her closely for lice or mites, especially around her vent area if you havnt already done so and treat accordingly.
There's also the possibility that she has had a soiled rear end from feces and urates. The urates in her feces would cause redness and irritation, eventually feather loss would occur or by her preening. This might be the case and it would be best to apply Nu Stock on the effected area and it will heal up in about week or two. She will regrow feathers after molt. The Nu Stock will also prevent picking and pecking as well.
Nu Stock can be found in the equine section at a feed store. Shake the tube well and wear disposable gloves when applying it.

 

[graceupongrace]

Is she going in molt? If so, you'd see feathers laying on the ground in the pen.
Have you observed any feather picking going on? That could be an issue and you'll have observe your other birds.
Also inspect her closely for lice or mites, especially around her vent area if you havnt already done so and treat accordingly.
There's also the possibility that she has had a soiled rear end from feces and urates. The urates in her feces would cause redness and irritation, eventually feather loss would occur or by her preening. This might be the case and it would be best to apply Nu Stock on the effected area and it will heal up in about week or two. She will regrow feathers after molt. The Nu Stock will also prevent picking and pecking as well.
Nu Stock can be found in the equine section at a feed store. Shake the tube well and wear disposable gloves when applying it.
View attachment 1536991

Is she going in molt? If so, you'd see feathers laying on the ground in the pen.
Have you observed any feather picking going on? That could be an issue and you'll have observe your other birds.
Also inspect her closely for lice or mites, especially around her vent area if you havnt already done so and treat accordingly.
There's also the possibility that she has had a soiled rear end from feces and urates. The urates in her feces would cause redness and irritation, eventually feather loss would occur or by her preening. This might be the case and it would be best to apply Nu Stock on the effected area and it will heal up in about week or two. She will regrow feathers after molt. The Nu Stock will also prevent picking and pecking as well.
Nu Stock can be found in the equine section at a feed store. Shake the tube well and wear disposable gloves when applying it.
View attachment 1536991

Thanks so much for your informative answer! I really appreciate your help!