This morning, I went out to feed and water everybody, and they all seemed to be their usual crazy, noisy guinea selves, including my only Buff Dondette male. I saw him eating and drinking, running around with the the others, there was no sign of illness, no puffy feathers, lethargy, discharge, etc. So, I went out and mowed the back pasture, and when I came back he was just lying there dead, not a feather out of place, no injuries, body still warm, all the other guineas still seem fine. Has anybody else had this happen or have any ideas? The bird in question was about a year old, and while I've had them kill themselves in stupid ways, I've never had one just drop dead before. Do I need to be worrying about something with the other guineas and chickens?