Identifying fertilized eggs

[Stoney Meadow Maple]

A friend called me yesterday for a few things, among others she wanted to buy some hatching eggs from me for her daughter to hatch this spring, they sell goat milk and wanted to add eggs to their repertoire. I will give her all the eggs she wants, but how do I actually know they are fertilized? Sir Winston favors the Pekins, but he's not above mounting a Rouen, i have seen him with a runner, but mostly its the Pekins. I see eggs being candled, but these are actively being incubated, should I just give her a mess of eggs and let her see what happens? Can I identify which ones are fertilized and which aren't beforehand?
Thanks!

 

[JacinLarkwell]

You have to crack them open and look for the bullseye

 

[nuthatched]

Crack open a few and look for the Bulls eye.

 

[cheezenkwackers]

I don't think it looks all that much like a bullseye. The duck egg on top is infertile, the egg at the bottom is fertile. You can tell by looking at the white dot on the yolk. If it is large and definite, like the bottom egg, it is fertile. So, like the others said, break one open.

 

[Stoney Meadow Maple]

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I don't think it looks all that much like a bullseye. The duck egg on top is infertile, the egg at the bottom is fertile. You can tell by looking at the white dot on the yolk. If it is large and definite, like the bottom egg, it is fertile. So, like the others said, break one open.

Literally the white dot in the middle? To me that looks like a reflection, but that is what i am looking for?

 

[cheezenkwackers]

 

[JacinLarkwell]

It's a white dot with a white ring around it

 

[Stoney Meadow Maple]

So essentially identify the size that are routinely fertilized and send them? I have about a week to gather and store at room temp, correct?

 

[cheezenkwackers]

So essentially identify the size that are routinely fertilized and send them? I have about a week to gather and store at room temp, correct?

Yes.

 

[cheezenkwackers]

It's a white dot with a white ring around it

I only have ducks but from pictures it seems like chicken eggs have a more obvious ring. I think the size of the dot is more telling. Infertile eggs often have a faint ring.