Molting or parasites?

[chickenmom664]

Two girls have this. Don't see any bugs at all. What else could this be. Only of my 21 have this

 

[Wyorp Rock]

Welcome to BYC.

Do you have a rooster?
How old is she?
How much space do you have in your coop/run?

If you have a rooster it could be damage from being mounted, I see quite a few broken feathers, it could also be from feather picking.

Molting can come in different stages, so I wouldn't rule that out, especially if you are seeing new growth and pin feathers coming in.



Molting:
http://www.the-chicken-chick.com/2011/12/molting-what-is-it-and-how-to-help.html

Mites/Lice:
http://www.the-chicken-chick.com/2012/08/poultry-lice-and-mites-identification.html

 

[chickenmom664]

She is approximately 2 years old. All of the chickens have a run about 15-20 ft by 10ft and for all the chickens we have two coops that take up the size of two stalls in our barn. We do have one rooster who is around 8-9 months. We have had one hen who looked liked this and she passed away.

 

[Wyorp Rock]

Keep watch on her, it could be molting but the broken feathers still remind of treading (mating) - a young cockerel like you have can be rough on hens, especially if they are lower in pecking order. Observe the flock to see if she is getting picked on, taking note of actions at night during roosting.

The links I previously posted are useful in helping to identify lice/mites, so check her over really well to make sure there is not an infestation.

Since she is loosing feathers and you don't mention seeing any pin feathers, she would most likely benefit from some extra protein like hard boiled egg, tuna, mackerel or meat in addition to her normal poultry feed. If you have them offer some poultry vitamins in the water a couple of days a week.