We had a new flock of 12 birds from May; 10 hens and two roosters (a barred rock, and a light brahma). We raised them from chicks; the brahma, though smaller, turned out to be the dominant one. It crows all the time. Today was the first time we heard the barred rock crow. He was just over 5 months old, and by far the largest bird we had. This morning I let the chickens out into the yard as usual, and gave them a breakfast treat consisting of two scoops of ice-cream and a bunch of fresh collards. Later that afternoon, my wife and I were pulling weeds around the chicken yard fence. Ten feet from us was the barred rock. He was walking in the grass with a few of the hens. Probably hunting grasshoppers. Without warning, the rooster flopped onto his side with a thud. His right wing trembled for a few seconds, then went limp. I ran into the yard to have a look, and the rooster was stone dead! It almost looked like the chicken had been shot. We sifted through his feathers looking for some sign of injury, but there was none. There was nothing unusual looking at all, aside from him being dead. The rest of the flock appears to be perfectly healthy, and were still doing ok when the coop was closed up tonight. I've searched through the forum about sudden chicken death, but I haven't seen any posts about this exact problem. I hope the chickens haven't got salmonella; it's been a week since I last bleached their waterer. We are in central Minnesota, so the likelihood of a toxic snake or spider bite is unlikely. Does anyone have any ideas about this?