Silly New Egg question of the day- verifying egg fertility

[possumblossum]

OK, I've read the articles and watched the candling videos in the learning center and I've read a couple of good posts on how to determine a fertile egg once you crack it ( you've probably seen the ones that talk about the bulls-eye)

So here's the situation. I'm not ready to start incubating eggs, but when I do, I want to make sure I'm getting as efficient as hatch as possible. Is there a fairly sure-fire way to confirm fertilization of a colored egg?

I have seven EE hens that lay both a pale blue and light brown/pinkish egg. (Yes, I have a rooster... so that's not the issue)

I candle them the day we clear the nesting boxes and then let them sit for a couple of days and candle again before refrigerating. Only occassionally do I see a definitive shadow like the one displayed in the learning center article, and then it's usually on the brown eggs. When I do see the shadow, I keep those eggs in a separate carton so I can assess my candling ability for when I start incubating.

Later when I crack the eggs for consumption, I check for the bulls-eye and note whether the egg is the shadow carton or non-shadow carton. Right now, I'm at about a 60% success rate on determining fertility with the brown eggs, but only about 20% with the blues. This encompasses both eggs that didn't candle fertile, but proved to be thus and eggs that candled with a shadow, but didn't have the bulls-eye.

Is there a more definitive way to verify fertility?


Thanks,
Justin

 

[abanjaf]

The only way to check for fertility before incubation is to crack the egg open and check for the bull's eye. No amount of candling can tell you whether an egg is fertilized or not. Once you place them in the incubator, you can usually see the "spider" of veins developing around Day 3 (although I prefer candling at 7 days), unless of course it's an extremely dark egg like Maran eggs or an olive egg

 

[Three Cedars Silkies]

Don't know if I'm fully understanding your post, but you cannot determine fertility of an egg by candling unless it has been incubating at at least 99.5 degrees for a minimum of 4 day...7 days is best.

The only other way to check fertility is to crack the eggs and check for the bullseye as you mentioned. If these eggs are from your birds, then you don't need to candle until you actually start incubating the eggs...you won't see anything.

 

[possumblossum]

Thanks for the feedback....let me clarify my post. On the learning center page for candling eggs, https://www.backyardchickens.com/LC-candling-eggs.html, there are photos of a store bought egg, a hatching egg a few day old, but not yet incubated, and an egg on "Day 1". The store bought egg is clear, the two hatching eggs that proved fertile have a definite shadow giving the impression that this a consistent development.

Apparently, I assumed too much; that's why I ask questions well in advance.

Thanks,
Justin

 

[abanjaf]

Okay, went back and reread your initial post and checked out the link you listed. The shadow that you mention in your initial post is simply the yolk of the egg. I have found that this is something I can see in my both my fertilized and unfertilized eggs. I wait until Day 7 of incubation before tossing any eggs. When I candle my incubated eggs that are infertile or possibly early quitters, they will candle clear like the picture shown for the store bought egg OR may candle with the shadow of the yolk seen but no embryo development noted. Hope this helps Truly the only wait to know is to check for the bull's eye on the yolk or incubating the eggs.

 

[possumblossum]

Excellent...the more I ask, the more I know. I appreciate everyone's timely responses.