I'm posting this question on my brother-in-law's behalf. They have a Blue Orpington rooster, Gus, about 4 years old or a bit more, who has exhibited subdued behavior for at least a week, and isn't eating much. He's lost quite a bit of weight. His comb and wattles are still bright, feathers intact. My brother-in-law says Gus smells necrotic but he can't find any fly strike or injury of any kind on him. He's walking and pecking around some, but is quite "off his game." (The fact that Gus let himself be handled, turned upside down, and completely checked out is unusual.) Poops seem normal. So my BIL gave him worm medication last night just in case, but does anyone have any other ideas about Gus's mystery illness? Thanks so much to anyone who might have a suggestion.