My Buff Orp free range roo was acting funny yesterday evening. He was opening his beak really wide a whole lot. He was still behaving normally except for this. He hadn't crowed since noon. We found him against the garage this morning. He had passed away sometimes in the night after midnight when we went to bed. Was his crop maybe impacted, you think? There was nothing else wrong with him but the beak opening. I checked and there wasn't anything in his throat and he seemed to be breathing normally, except now and then he'd make a croak sound. Any ideas?