A month or two ago I bought 4 chickens at our local feed store. I bought two Silvertipped Wyandottes, one Gold Wyandotte, and one Americana (or at least thats what they told me at the store). About a week after I brought them home, my white chicken (or yellow at the time) the americana, started having issues pooping. Her anus was leaking poopy and the poopy dries on her skin. She is pulling the feathers out around her anus. At first I thought maybe she was constipated, as the weather was in the 90's for a few days the week after I brought them home, so I made sure they had LOTS of water, but that didn't seem to help. She is able to poop, but she makes discomfort noises when she does. Like its hard to do it. I bought some antibiotics (Sulfadimethoxine soluable powder) at the feed store and gave her that for the last two weeks but I'm still having issues. Every night I wash her butt off but nothing seems to help. What can I do for her? Here are some pictures of what I'm dealing with. I just gave her butt a bath, so thats why she is wet. Any help you guys can give me is greatly appreciated, I just don't know what to do for her!