What are Fertile Eggs

Fertile EggsEggs which have been fertilized, can be incubated and developed into chicks, as long as the eggs are not refrigerated.

A Female Bird can lay fertilized eggs from anywhere to 2 days after mating up to 3 weeks after mating with the Male. The oldest and easiest way to tell if an egg is fertilized is called candling the egg. It is literally holding the egg up to a lit candle {not to warm it, but in order to see inside of the egg}.
Turn the eggs to a new position once daily until placing in the incubator. Hatchability holds reasonably well up to 3 weeks. Therefore, do not store eggs more than 3 weeks  before incubating.