I started out with 11 hens, 3 red stars, 3 buff orpingtons, and 5 buff/welsummer crosses. About 2 1/2 weeks ago I found a red star dead in the coop, her intestine was also hanging out. I figured it was prolapse and a fluke, but a week later, it happened to a 2nd red star. Later the same week, one of my crosses died, and now a second cross has died also. The second two that died did not have intestines outside of the body, but where the egg comes out was very bloody and kind of ripped open. I have lost 4 hens in 2 1/2 weeks! I'm not sure what is doing it. They seem perfectly fine otherwise, eating, drinking, laying. I have never seen them pick at each other. I feed them strictly layer pellets and they have access to oyster shells. They get 13 hours of light. I turned back the lamp thinking that maybe they were overlaying. I'm not sure what else to do, any ideas?!?