How do you know an egg is fertile?

[csaylorchickens]

I have a broody hen and figured I would let her Try to hatch a batch of eggs for me.
My friend has a rooster and the rooster has been mating with the hens daily. She also said almost all her eggs are fertized.
So I got six eggs from her to put under my hen.
How do you know if the eggs are fertilized? Should I try to candle them on day 10 to see if they are viable?
I would hate to leave her broody if the eggs were not taking and then I can break her of the broody behavior if it's not needed.

 

[SamCox]

You can tell if an egg is fertile on day 5 - 7. When you candle them you should be able to see the veins. You can also crack one of the shells open and look for the bullseye dot Good luck with you hatching

 

[Pork Pie]

Personallly, i just leave the mother hen to it. On day 21 (assuming its early in the morning, or i find the chicks at that time) i will leave the non-hatched eggs for another day and then assume any remaining eggs are infertile. I guess its our curiosity (and impatience) that keeps us intrigued by the whole hatching and development process, so i understand why you wish to know.

Good luck with your hatch!

 

[csaylorchickens]

Thanks everyone! I was reading about egg exploding and goo getting everywhere I want to avoid that if I can
I will let her to it and just make sure every day that they have exploded! I'll do one look at 10 days then call it good

thanks for the advice! I had to give her water via dropper two time tonight it's hecka hot 100 so I used an umbrella and opened up the coop for ventilation
Hopefully it cools down soon!