We have a Buff Orpington that has one eye swollen shut and dark crud coming out of one side of her beak. One side of her face appears swollen, like it's infected and the other side looks fine. She seems to have a healthy appetite and is hanging out, but keeping to herself. She is pretty much a loner anyway, as she if the only Buff that we have. Our chickens free range. What do you think her problem is and how can I treat her effectively. Thanks for your help!!