Folks: After some agonizing, I decided to cull and perform a necropsy on this very thin hen who had not been gaining weight despite being isolated with starter crumble for a week. I was worried that I wouldn't be able to tell what was wrong, but I'm sure now. She was massively egg-bound. Probably should have culled her sooner. The DIY necropsy was a good learning experience, after all. I'm convinced that the egg binding was what was ailing her, but I did find several adult roundworms in her intestine. Probably about a dozen (in the last photo). I know that this is a subject of great debate, and I'm wondering whether to treat the rest of the flock for roundworms or to let them be. This is the only hen who is underweight. The rest are doing well, and don't have the protruding breastbone that this one hen had. Would it be at all reasonable to allow this moderate worm infestation to continue as a symbiotic relationship, rather than dosing the flock with chems? My flock of about 20 free range on an acre or so of pasture and forest. (Apologies for the slightly out-of-focus photos. **** you, Tim Cook!) .