I have a young rooster that was "roosting" all morning and when I came home this evening and went to check on my babies I found him sitting on the ground in the pen, wouldn't move, seeming very ill. Hens get egg bound, which I have not had in 3 years, sour crops, and if there is anything else I have not experienced it, but what do roosters get sick from.
they can get sick from lots of things. You need to provide more info and post in the disease forum ETA read this first