Came home today to find one of our hens dead in the nesting box. My wife found her earlier in the day. She was one of our favorites so of course we were sad. I did an autopsy and didn't notice anything weird inside. No enlarged organs, stuck egg, normal looking internal organs other than some spotting on the liver. Meat looked fine, but because we don't know if it's an illness of some sort, we're not feeding her to the dog. She was bullied by the lead hen and would sleep in the nesting box, I even had to manually take her out all the time. Knowing what she died from is of course a curiosity for me but also I'm worried about the others. She had no open sores that I could tell. Should I treat them all with some kind of medicine like a dewormer or an antibiotic?