I went out to feed the girls as usual and I noticed that my one hen's "Bawk" sounded a little funny. Then I noticed that it appears as if the side of her head has a yellow tinged something smeared in her head feathers. There is also a tiny yellow hardended bead on her beak by the nostil. My guess is that she has something brewing, I really don't have anything set up right now to seperate her ( I can get something going tonight ). I have Polysol vitamins, and Terramycin at home, what do you suggest. She is my most skittish and I can't seem to catch her to get a better look. Can I put something in the water and treat everyone too? Otherwise she's eating and seems fine.