Just baffled here. Unlocked the henhouse this morning and every one of my 11 layers (except one who had hatched some chicks, and her 5 chicks) was dead in the coop, apparently unharmed. No feathers missing, no blood, no wounds, nothing. The only thing I can think of is they were poisoned somehow. Spoiled feed? I've seen chickens eat a lot of crap...literally, so I'm not sure what would otherwise have killed them. Any suggestions?