One of my roosters developed a black spot on his neck by his head, and on the other side of his face, just in front of his eye. The skin around them looked like it ended at the edge of the black area, i.e. it rolled at the edge. They both swelled up, but the one on his neck is now the size of a ping pong ball, and the one by his eye swells from the beak back to include his eye. At about the same time another rooster died. He had the same black spot errupting thru the skin, but on his belly. Then a hen died and had the black erruption on a feather follicle on her wing. This all started after heavy rains when the chicken run turned to mud. It took a few days for me to get sand to raise the elevation above the rest of the area. We have a nearly flat acre of clay, slow drainage & absorption. The muddiest area was next to the compost where I also add the litter from the coops. So I'm sure they were walking in bad stuff. Anyhow, once the area was dry, and all the coops had fresh shavings & cider vinegar added to the water, the deaths stopped, but the rooster with the swellings remains. He was running with the flock, eating & drinking fine, but the lumps don't go away. I don't know whether to cull him. He is under weight, & I can't afford a vet for a rooster that may have ended up as dinner anyway. I have him in the bathroom now where I can soak his lumps in warm water with betadine and be sure he's eating enough. It's so much harder to kill a chicken I've treated for a while than a strong healthy one for dinner. Both are difficult, but eggs WILL hatch out roosters half the time.