we have 14 hens, most are a year and a half old, and 2 are ~7 months old. A month ago the ALL stopped laying eggs. They look molty. They had a spring molt where egg production dropped by 2/3, and gradually came back up to ~80%. Not all grew ALL their feathers back. then last month they stopped completely. No cough or sneezing, no diarrhea, no other symptoms. a few still have areas with sparse feathers. Coop is clean, run is dirt (pretty large), and fenced, due to heavy predators. We did throw away and replace food when they first stopped laying, just in case there was a problem with it. We are now getting one to two eggs some days, none other days. One australorpe was weak last night, and dead this morning. No outward sign of injury. The hens ahd not acted "off" before that. What could be wrong with them? How should we treat? Would a broad spectrum antibiotic be helpful? Should they be wormed routinely? (I have no knowledge that they HAVE parasites, but wonder if treating anyway would help?) HELP! My daughter raises these hens for a girl scout project to provide fresh eggs to soup kitchens. So they are her pets, for a good cause! Thanks!