Our barred rock rooster was lethargic when I got home this afternoon. He was fine this morning and at noon. Got home and he was laying next to the coop in the shade, did not get up when I went toward him. He will only move if I pick him up. He is real slow and not active. Laid back down right away. There was a lot of watery poop almost clear behind him. He is free range during the day, locked up at night. We have 30 other chickens he is the only one acting that way. He is 6 months old and one of the oldest ones. Please help, thanks.