Impacted Crop, maybe?

[Americana]

It sounds like sour crop to me as well. I had a bantam malay cockeral with sour crop. I put apple cider vinegar in his water and he was fine a couple of days later.
You have to catch it early! The day before treatment I noticed he was not crowing-That was a good reason for me to check him. You get to know each chicken and their behavior and know if they aren't acting right.
I have lost a couple before , because I didn't know the symptoms, and by then it was too late!

I have a hen with a large crop like that and so far I haven't had any problems ( Of course I just got her last week at a swap) So we will see.

Good luck and keep us posted

 

[MarieNC]

I have a girl with recurrent crop problems. She has had two surgeries for it - the first one to have the crop emptied, the second to have it resected b/c it was all stretched out and would not spring back. Now she wears a crop bra most of the time - I got it here:

http://crazykfarm.mybigcommerce.com/products/Birdy-Bra-Crop-Supporter-{47}-Chest-Protector.html

My only problem with them is that the ties stretch out quite a bit over time, but it's no big deal. Actually my profile pic shows Cornelia Marie with her crop bra on, but it may be hard to see. She tolerates it very well for the most part.