I'm thinking it might be sour crop, which I don't know how to treat by the way. She's hatched this april, flock of about 40 hens, 3 cocks. She is a leghorn. Had all her vaccinations. First noticed symptoms this morning. She was huddled in a nesting box, sleepy, thought she was going to lay. This afternoon she is still in the box, moaning slightly. Had a look at her, she's had some yellow poop, medium runny. She won't drink or eat and pays very little attention to the world. She has almost no fight in her. her crop is bloated and squishy (not hard like crop bound). She has a mucus in her mouth and laboured breathing. Her breath smells like a cross between vodka and sour-dough. They won't go outside in the snow, so they spent the last two days inside and today is their first day out. I thought that they had enough gravel to last two days, but apparently they are all out this morning. There is also the possibility of a toxic plant in that pasture as someone always seems to get sick when I let them out over there, but they all stay healthy in their other pasture. Please help. She has almost no response to me now. Even if I cannot save her, I would like to know what's up so that I can prevent it or treat it in future.