One of my buff orpington chickens died yesterday. I thought she seemed a little funny the other night as she was in the nest box and when I tried to move her out she stumbled a bit. I thought it may have just been her being tired as it was kind of late. Last night I didn't find her in the coop. She was in front of it under the ramp looking almost dead. I took her inside. I didn't know if she was egg bound so I let her sit in a warm bath. I took her out and wrapped her in a towel and sat with her. She then starts letting out a noise, twitching, then puking a pale liquid. She does this a few times before she passes away. I looked at her and realized her breast bone was super exposed and she had lost a Tom of weight. You would never know with all of her feathers making her look normal. Her crop did not feel hard or anything. Her abdomen was super bloated but it was soft and there was no stuck egg that I could tell. I felt the best bone on another chicken today and it wasn't anything too bad but I'm afraid she might be losing weight. Any ideas on what this could be or how to treat the rest? I'm terrified the rest of them might be affected.