my first post is a bummer!! I've had chickens for going on four years and this is a first. i have an otherwise healthy partridge silkie who in just a few days developed a scabby patch on the back of her head and some on top. i thought it was the other birds that did it, but now i'm thinking maybe parasites? no blood, no scratching. just like a dry callous patch. whats also very notable is that the other birds have very suddenly bumped her to the bottom of the pecking order. she is isolating herself and they are isolating her too. all other birds are in fantastic condition. there was a recent change in pecking order but she wasn't really part of that. i cant see any mites visually. perhaps an infestation that i cant see? while it is really cold up here in the northeast right now, i do know that infestations can happen regardless. thoughts? she is otherwise eating and peppy.