I have 15 hens, my oldest hen stared out with diarrhea and three more have it now. They are loosing feathers on their bums, although my oldest one seems to be over it and her feathers are starting to grow back now. There are NO signs of: blood in poop worms in poop lack of appetite lethargy They are all eating like pigs and I have not given them any treats or scraps in a week to see if this will clear up. My hens don't free range and I have never wormed them. Any ideas to what this is and anything I can give them to stop it? I'm really concerned about my speckled sussex - she's had it the worst and the longest, but she shows absolutely no signs of being sick. Thanks.