So how do I know if an egg is fertile? There are two easy ways to check.
The first and most obvious way is to stick the eggs in an incubator. After seven to ten days, you can tell if a baby chicken or duck is developing inside the egg by candling it. Candling simply means shining a light into the egg, and it enables me to see if there are veins in the egg. Veins = a growing embryo and a fertile egg. Here's a link to a page that shows what I'm looking for.
I tend to use a quicker method to monitor fertility at the beginning of the season and as a spot check throughout the year. Here's how I do it:
First, I break open the egg/s I want to check. It helps to check fertility at breakfast time so I have something to do with all those eggs I break open!
|A very fresh Ancona duck egg. Look how firm the white is!|
Take a look at the yolk in the above photo. Do you see white dot in the middle of the yolk? Notice that it is surrounded by another circle of white like a sort of halo.
|A closer view|
Here's a closeup of the same yolk. It looks like a bullseye, doesn't it? When I see the bullseye, I know my drakes are doing their jobs - this is a fertile egg. The white spot is technically called a blastoderm and it would develop into a duckling if I had incubated it.
Infertile eggs do not have a bullseye. You can barely see the blastoderm at all; it just looks like a tiny white speck on the yolk.
At the beginning of the hatching egg season, I break open and examine all the eggs my ducks lay. I only sell hatching eggs when fertility is fabulous and the ducks have started laying like gangbusters. I will never be the first person to sell hatching eggs each season, but I promise you that anyone who buys hatching eggs from Gust Front Farm will never have reason to complain about fertility!
~Emily, Resident Crazy Poultry Person