I have a laying hen and I came back from feeding our ducks, and found her standing in the middle of our coop stretching her neck out and gasping for air. I thought maybe she had something stuck in her neck but I didn't feel anything, then I felt her crop and it's SOLID. I fed her drops of veggie oil and water through a syringe and she's no different. Her eyes are closed and she changes from sitting to standing. It sounds like she gasps for air and then as she stretches her neck, squeaks come out. I think it may be impacted crop or sour crop but I'm not sure what sour crop smells like. I can't tell if she has a bad smell or not.