When I was young and we had chickens, we had a large run with natural ground in the woods that was not covered and other than an occasional hawk or the great horned owl, never an issue...Here, I have the coop, the run fenced all around...a teacher at my school said I need to put hay in the run because when it rains they will get some foot disease. I have never heard this before...opinions? Advice?? Thanks~ Lynette
maybe bumble foot ?
but Welcome ask what the heck of your friend, chickens are closest to prehistoric as one might get they eat things that would make most of go 
but they give us very tasty breakfast, lunch or dinner




