A lot of chicken diseases seem to have puffing up / eyes closed as a symptom, however I was hoping a pic might help with diagnosis? my Chickens are in a chicken tractor that is moved every day. over the last 6 months or so I have lost several chickens who gradually got weaker / puffed/ lost all their weight and then died. I have 2 ducks with them. ( don't know if that matters) poop looks normal / no visible parasites/ crop is not impacted / crop is not mushy or watery/ eyes are clear / coop is cleaned regularly / food and water available. I dont know whats going on. any help would be appreciated.