I have no idea, I have never heard of that before. I am facing a dillema right now as well. I think maybe my muscovy might have started laying, I may have a duck egg or two in my incubator and have no idea how to tell the difference other than wait. lol.
Keeper of 1 son, 1 man child, 1 step-son, 5 beagles, 1 boxer, 1 Chinese Crested, 3 DSH cats, a flock of chickens, 2 muscovy ducks, 1 Saanen doe, 1 Oberhasli doe, 1 Saanen buck, and 1 Nubian buck.
Keeper of 1 son, 1 man child, 1 step-son, 5 beagles, 1 boxer, 1 Chinese Crested, 3 DSH cats, a flock of chickens, 2 muscovy ducks, 1 Saanen doe, 1 Oberhasli doe, 1 Saanen buck, and 1 Nubian buck.

















I have not noticed movement in my fertile egg yet, but I haven't candled it very much.







