I recently got a question from a reader who wanted to hatch some of his chickens eggs. He has 8 chickens and 1 rooster. He currently has collected about 20 eggs and is wanting to know if they are fertile, so that he can put them in an incubator.
While I am not allowed to have roosters due to my neighborhood covenants, I have always kind of wondered if I would get a fertilized egg before I get rid of them. {We order chicks and usually get a rooster or two out of the bunch–we get rid of the rooster pretty soon after we know that it is in fact a rooster, though.}
So, first a little talk about the birds and the bees {only, in this case, it really only involves two birds}. In order for an egg to become fertilized, the rooster and the hen have to have mated prior to the formation of the egg. If this happens, the hen will lay a fertilized egg. This probably goes without saying, but if you don’t have a rooster, you will not have any fertilized eggs…ever. A hen can lay fertilized eggs from anywhere to 2 days after mating up to 3 weeks after mating with the rooster.
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}. You can also use a very bright small flashlight. If the egg appears opaque, it is probably a fertilized egg. {By opaque, I mean, you can’t really see through the egg or it is much cloudier than all of the other eggs.}
As a side note, just because an egg is fertile, does not mean it will become a chick. It must be properly incubated by the hen or under an incubator in order to develop into a chick. After 3-4 days of incubation, you can candle the egg again. You will see that it has started to form–it will look kind of like red veins spreading throughout the egg.
A fertile egg layed by a hen that is not incubated is perfectly safe to eat, and unless you are paying super close attention, you will never know the difference. Once you collect the eggs and put them in the fridge, the development completely stops.
I hope that helps, and if you do get some baby chicks, send some pictures!
~Mavis
Want to read more about our flock? You can find all my chicken posts HERE.
Looking for a few good books on chicken keeping? These are my favorites:
- The Chicken Encyclopedia: An Illustrated Reference
- The Chicken Health Handbook
- Hatching & Brooding Your Own Chicks
- Gardening with Chickens
This post may contain affiliate links. These affiliate links help support this site. For more information, please see my disclosure policy. Thank you for supporting One Hundred Dollars a Month.
