I had one of my guineas lay an egg the other day. A friend who was checking on them while I was out of town put it in my fridge. I would have left it in place. Anyhow, I certainly doubt it was fertile...and I don't want them to set anyway (I have an incubator). I WOULD like to get them to keep laying and I put a few dummy eggs in the coop in a pile but the next day they were all scattered. I put them all back and today they were all scattered again. I couldn't find any dummy guinea eggs and I didn't know if that was because dummy chicken eggs work fine or if NO dummy eggs work with guineas. I know with chickens a golf-ball will work but since guineas aren't as domesticated I wasn't sure if they would even fall for a guinea egg. I book I have says to leave a few eggs in place, but I don't want them to spoil in the coop.