Our Blue Andalusian (tango or cash I can't keep them straight) has a big bare spot on her chest. My wife has caught the other chickens plucking her feathers out but not attacking her. No broken skin. No mites. The just started laying this month. It looks distended. She is otherwise acting normal. Is this a molting thing? Not sure why the others are eating her feathers. They have plenty of oyster shell and grit in the run & food. Meal worms and Oats Anything to worry about???
How old is she? If she's 18 months or older, it could very well be molting. But molting usually has a nice uniform array of pin feathers in the bald area. Unless the other is nabbing the pin feathers as soon as they emerge. What I would do is paint the fleshy area with Blu-kote to disguise the nude skin, which is irresistible to chickens. You might also spread some Rooster Booster pic-no-mor on it. Or you can concoct something similar with Vicks and grape Kool-aid powder. By the way, that area is the crop and it's normally distended. It's all the more conspicuous due to the visual illusion of the lighter area appearing to be closer than the surrounding dark area.
I would also check her crop on the roost at night then first thing in the morning before feeding to make sure it's emptying.
