Chicken found dead

[Colberon]

This morning my husband found one of our 6 month old pulls dead inside the coop and I’m hoping someone can give me an idea of what might have happened...she hadn’t shown any signs of illness leading up to this morning, except last night when my husband went to get their water out of the coop for the night (around 10 pm) she was laying over next to the door, but he didn’t find this too strange because for some reason her and the other two pulls and one rooster refuse to roost but choose to sleep on the coop floor; is it possible this caused her to pass? Attached is a picture of our setup, two coops, one house 3 chickens who are about 18 months old and the second coop had 3 pulleys and a cockerel and we lost the one girl this morning. They are fed feather fixer pellets, daily treat if mealworms and have choice oyster shells and grit available. I believe she may have started laying recently and layed nearly dail for two weeks and then quit, thinking maybe egg bound? We live in Maine. The fenced in area is shared by all.

 

[MickWithChicks]

At that age with no other signs of illness, you're probably looking at an egg laying issue such as egg binding or EYP. As chickens start to lay at that age and often have some glitches in their egg laying process, I'd almost bet on it.

You could perform a necropsy to be sure, but I've had a few cark it at that age and it was exclusively due to egg laying issues.