Well at least 3 for sure. I've got 13 eggs in my bator on day 6 and decided to candle them tonight. So far 3 have veins, 4 seem to have nothing, 2 are too dark to see, and finally 4 seem to have a dark ring all the way around the egg. I'm so exicted. One of the eggs I had a feeling wasn't fertile, and the other 12 were left out in the cold (about 20 deg or less) for a few days.