My silver-laced wyandotte gets poop stuck to her fluffy butt feathers a lot and she makes it worse when she dust bathes and gets it all matted up with dirt. What I usually do is I take her a shower and loosen up all the poop and dirt and trim off the feathers around her vent area and below. Well, this time while I was checking around through her butt feathers I saw a white/yellowish crust on her skin around the base of some of the feathers, some cluster of something coming out of the sheath from the feathers, and some sort of mite and/or lice crawling around, luckily I didn't see many. Here's an image but click here to zoom in completely. At first I thought maybe that cluster was just new down feathers coming out from the sheath, but after looking at some photos I think it has to do with the mites/lice. Are they eggs? What about the crusty skin? This is my first time dealing with lice/mites with my chickens, so I'm going to buy some mite dusting powder or DE if I find any at our feed store or bird farm. I want to spread it around our chicken coop (we use construction sand as bedding), their sleeping spots, nesting buckets, and in the dirt where they dust bathe outside. From what I've seen, I should just apply it on their skin and rub it in, right? What else should I do and what do you recommend? Also, other than having some critters crawling around her butt, she's a very energetic chicken, eats and drinks well, and lays eggs too.