I hope someone can help me with this. This morning before I went to work I noticed that one of my hens had a scabby area right above her vent and then saw that she has a bald patch below her vent. I went to work and started researching what it might be. During the day my husband went out to change out the water and collect eggs and noticed she had blood on her in that area. he brought her inside. I got home and checked her out. The blood was dried in her feathers but seemed to have come from that "scab" area by her vent. I went out to the other hens and inspected everyone thoroughly. Another hen has that same "scab" above her vent and everyone seems to be losing feathers under vent area, in what I call the "skirt" area (they are Buff Orpingtons). I had to actually move their feathers to see the bald spots. They are not as bad as the first mentioned hen. I saw no bugs of any kind. The only thing I can say I noticed was the shaft of the feathers looked dirty, like they had taken dust baths, which maybe they did. But maybe its a sign of a type of bug too? I've seen pics with lice congregated at the shaft of feathers and it did not look like that. I use DE, but not enough? This is my first time having chickens. maybe I wasn't liberal enough with it through the winter, thinking these things don't live in extreme cold? I don't know, but I'm learning the hard way I guess. I have seen posts where people suggest permethrin dust or even ivomectrin pour on to treat each bird. I had to wash said bird to get the crusty blood off and inspect more. She is in the house for the night. Its supposed to get to negative 18 tonight, I couldn't put her back being wet. I'm hoping more experienced chicken owners can help and point me in the right direction. At this point I am only guessing that it is lice or mites. Any info is greatly appreciated. The first two pictures is before washing. You can see the "scab" on upper part of her vent. This next picture is of her bald spot. I tried to get most of the blood off that had dripped down into her "skirt" from the area by the vent. It didn't look this bald until I had washed her. Edited to add last picture: Thank you in advance!