Please post some photos of the sick bird, her poop and your coop/run.We feed Purina layers, 5 grain scratch and table scrapes vegetables some melon...also different kinds of store bought treats...the girls were just kind of starring and very lethargic......their about10 months old...I don’t see mold anywhere...they don’t free range...large run with coop which I lock up at night... I think I have a fourth bird sick...thank you for your advise...
Lethargic and staring?
What does your feed smell like - how are you feeding? Look at the feed that is in the feeders - does it have green or white tint to it?
Where are you located in the world?