I have 2 seperate coops. There was 6 chickens in my first coop. And, 4 in my second. The 6 were my first established flock and they didn't get along with my other 4 so we seperated them. These chickens have never been free roam- they prefer their coop. The coop is secure. Locks on it, and wire- there is nothing but bugs that could get in. 10 days ago I found one of them dead- with what appeared to be a broken neck but upon reading I'm wondering if chickens necks just get floppy when they pass We watched the others and they showed no signs of illness. However, yesterday my favorite rooster in that coop- a silkie- had fell over dead. My fiance didn't bury him until that afternoon and he was missing his feathers. We assumed the others had attacked him for some reason. Until this morning- when I went outside to feed them and the other 3 were dead too. All flopped over on their sides. When I go to bury them is there a way to find out what is causing this? My other 4 in the other coop are fine. I am heartbroken.