Well just a quick thought. All summer when I went into my coop, (Which is totally enclosed) and feed and water my chickens I would get these tee tiny little bugs on my arms and legs. Everyone told me they were chicken mites (lice ?). I treated for that and they were persistant. I cleaned out the whole coop and I have a large hallway inbetween the coops that I keep the feed and some other stuff I need. I realized that the bugs were coming from the feed in the bag and not from the chickens. I bought a big garbage can with a tight fitting lid and emptied the feed into it and keep it tightly closed and dont have a problem anymore. I guess they were somekind of feed bug. Anyway, we are bug free. Just saying.