Hi FarmGirl -
My dog attacked one of my hens a couple of weeks ago. We have since rehomed the dog.
As far as my hen, she was torn and bloody everywhere. It seemed to hurt her when I tried to put anything on her wounds and the ointment I had made her feathers stick down, which I figured couldn't feel good, either. I have a large bottle of betadine that I got at the feed store for $16.99. I filled the sink with warm water and poured about half the bottle in, so it looked kind of like weak tea. I soaked her in that for about 15 minutes. I actually soaked her twice about three days apart. I figured that way the betadine got to whatever cuts and scrapes I couldn't see. I kept her in the house for a few days and fed her extra protein (mostly mealworms). It's two weeks later now, and she's doing great. I still bring her in at night because she lost so many feathers including the fluffy down ones that would keep her warm. During the day she only goes out with her apron on, so the guys won't reopen her cuts.
Anyway, if you have betadine, it might be a good idea because you may not see all the damage under the feathers and this way everything gets treated. You just have to make sure you dry her well with a hair dryer on low heat so she won't get chilled. If you put your hand in between the hair dryer and her, you can make sure it's not burning her.
Good luck!!