What could this be

[Tristan l]

I just bought started pullets and one has a patch of skin that does not have feathers and it is very rough and i was wondering if someone could tell me what to do

 

[HeritageGoose13]

Where is this on the pullet's body?

 

[Tristan l]

It's near the tail feathers on her lower back

 

[freeportchicks]

Can anyone help him out