My 7 month old ameraucan hen died this morning. She was fine yesterday and looked find when I locked them in the hen house last night. When I went to let them out of the chicken goop this morning she was in a nesting box panting so I thought she was laying here first egg. She has not laid an egg before. I went back 2 hours later and she was dead. Any ideas? Do you think it was an impacted egg?