So 2 days ago I was feeding my chickens. Everyone was fine and the next day I noticed my rooster going into the hay loft (20 ft up) to roost and I heard a very loud smack noise. I assume he hit something on his way up or from landing. The next day (yesterday 16th) I noticed him limping and eating with the hens. He avoided complete pressure on his left leg, but was still getting around with it. Came home from work later that night to find him laying in front of the barn door in the wind. (Where I am it's snowy and was 25F last night).. he was laying in the dirt alone. I brought in in the house away from my 3.5 week old chicks and put him in another room in a large box. He drank some water (and gatorade) cause I didn't have electrolyte or mineral water at that time. He didn't eat. He was very quite and as the night continued he was more lethargic. He wouldn't walk or stand. Only on one foot he could grip my fingers when I pressed them on his foot. He was very weak and I noticed he had lice also. His comb was red, but seemed slightly faded compared to wattle and his comb was hot to touch. He also pooped liquid, but I've read chickens will do that to cool off.. my house is around 70F compared to 25F outside. I did ..at 2 am.. go to the barn and sprinkled Red Lake DE (it is food & feed safe) around and patted a few hens I could reach. I noticed this am he was still weak. And he had congestion that you could see dripping out of his mouth when he lowered his head. He also had a mucus in it. My rooster died this morning just after 11am. What killed him and so quickly?? All other hens are ok seeming and acting within normal behaviors. Feed is cracked corn, free range, meal worms, and I gave them some wheat bread on the 16th. I feel like he could have had a few issues. He was an 8 month old Australorp rooster I raised as a chick.