Embryos have survived at temperatures below 90°F for up to 18 hours. You should continue to incubate the eggs after the outage; then candle them 4 to 6 days later to check for further development or signs of life. If, after 6 days, you do not see life or development in any of the eggs, then terminate incubation.
How long can fertile eggs survive without heat?
As a general rule, fertilized eggs can survive for a maximum of 7 days under 70 °F (21 °C). A temperature under 28.4 °F (-2 °C) will kill the embryo inside the egg. The cell division of the fertilized egg slows down below 79° F (26° C) and completely stops below 70° F (21° C).
Can eggs get cold and still hatch?
Eggs which have been subjected to freezing conditions (in the coop or in shipping) will have suffered damage to their internal structures and are highly unlikely to hatch.
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