This morning, Steve asked me an excellent question on the Dúagwyn Facebook Page. How do you know when an incubating egg is nonviable? The simple answer is: I don’t, but I’m surrounded by generous, experienced people who do.
The incubation period for chicken eggs is only 21 days, a very short time to go from zygote to fully-functional, independent being, although it doesn’t seem so to me at the moment. This remarkable transformation goes a little something like this:
As you can see, there’s a whole lot of growing that needs to happen each and every day. We can’t see the development as it’s happening inside a shell as graphically as above, of course, but we can see a shadow puppet show of it, in slow motion, through candling. Candling is the shining of a bright light through the developing egg, revealing silhouettes of growth, like this:
Candling is made much, much more difficult when one of two kinds of eggs are hatched:
- Very dark brown eggs, because the depth of colour of the bloom can make light penetration meager. Eggs such as these are laid by Marans and Welsummers
- Blue-shelled eggs, because, unlike all brown eggs, no matter how dark, the shells are blue all the way through; it’s not just dark bloom painted onto a white shell. These eggs are laid by Easter Eggers, Araucanas and Ameraucanas.
I am hatching Marans and Ameraucanas. Getting the picture? Because I’m not. There are special, high-intensity candlers for these kinds of eggs. I do not possess one. I will be in the market for one for next spring when 4.0 comes into the world, which presumes there will be a 3.0.
But…I grow maudlin.
What’s a freshman hatcher to do, when she can’t even see into her eggs properly? She guesses, she asks questions, and she waits. A lot. Especially when the eggs being evaluated were purchased at considerable cost and shipped considerable distance, and they’re not all hers.
Why not wait until hatch day, then, and just see what happens? As it turns out, very, very bad things can happen. A nonviable egg, dead, essentially, kept at a steady 100-degree heat over the course of three weeks might well explode, contaminating the other (live) inhabitants of the incubator, and, according to all reports, rendering your home inhabitable for quite some time. This is to be avoided.
To toss or not to toss? A difficult question, at the best of times; a damnable question when a virgin hatcher with failing eyesight is looking into dark, murky eggs. There is a time, however, when dark realities can no longer be avoided. On Day 18 (where 3.0 is today), a viable, incubating egg should be nearly full with chick, the yolk almost completely consumed. Save the air cell, there should be almost no light going through the shell when candled, thusly:
So, if on Day 18, one should see this while candling…
…one would need to assume that the embryo, once viable, has “quit” for one reason or another decreed by Mother Nature in her ineffable wisdom. I removed ten such eggs last night after candling. It was painful.
I have two eggs in the ‘bator still which I am 90% sure are nonviable; they look much more like Day 14 eggs than Day 18 eggs (which is to say half full), but I haven’t the heart or the stones to toss them.
We are in the final hours of Day 18 as I write, and still no internal pips that would signal the beginning of lockdown, all of which I will go into in more detail when it happens.
Now, if you’ll excuse me…I have to go candle.