In the Brooder
Mar 16, 2018
Today is day 10 with 10 speckled Sussex eggs in our small incubator. The eggs are all laid on their sides, and there is a circular dish in the center of the incubator with some water in It. Each egg has its fat, rounded end at the center and the pointier end at the wall of the incubator.

We candied on day 7. I noticed a “nucleus” floating (and moving around) on 8/10 eggs. The other two did not have a nucleus, or “dark shadows,” like the rest, and they let MUCH more light through & the consistency inside the egg appeared more watery and fluid. We assumed these two are infertile but they remain in the incubator still.

Today, we candles (day 10) and 2 show no signs of change, and 8/10 still show “nucleus” and show actual movement! (What is the moving around? Is this the embryo floating or the chick actually moving?)

Since the eggs lay on their side, I guess the air pockets all formed lengthwise on each egg, so 50% looks like air and 50% looks like a dark shadow.

Please note the added picture— as shown, the light side seems like air. The room is dark and the only light is coming from the candler. The lighter side of the egg stays in place as I turn the egg around, and the darker side does as well.

Thanks in advance for all help!


  • 81DC1455-CADC-4A7F-B958-924D555FE823.jpeg
    272.1 KB · Views: 15
Does your incubator have an automatic turner? Or are you manually turning the eggs 3x a day. On your photo not sure what going on in there but looks like veining.
You aren't doing anything wrong. I don't think that space is the air cell - there's still quite a bit of albumen at that stage (the egg white) as that's keeping everything moist until hatch day. You are only halfway through.

This is a great site to follow along with full of great information and candling photos to compare yours to: https://www.raising-happy-chickens.com/incubation-day-10.html

The movement you are seeing is the embryo reacting to the light and wriggling about. Try candling from the fat end and see if you can locate the bubble of the air cell. Sometimes they can get dislodged if the eggs are shipped to you (any sharp jolt can do it) and end up in an odd place but many chicks have hatched successfully with a dislodged air cell. You need to find it to ensure that it is growing large enough. If it's looking too small you can take out all water and run the incubator dry for a few days to help them catch up. Have you got a gauge measuring the humidity in the incubator at all? It should be around 30%ish (the amount needed can vary due to peoples unique climates). It's important the air cell grows large enough as it needs to sustain the chick between the internal and external pipping stages. Here's a good chart to compare to:

Does your incubator have an automatic turner? Or are you manually turning the eggs 3x a day. On your photo not sure what going on in there but looks like veining.

Yes! We turn 3-5x a day and rotate which side they are on overnight. This egg has movement inside. I have a video of the movement here:

But the form of the “air cell” worries me. All of my eggs are the same— vertical//lengthwise air pockets and I’m afraid It will end up hurting the chicks chances of a successful hatch.
That's not air pocket; that's the part of the egg still not covered with the chickens vascular system. It will grow into that area later. It's fine.

It seems that incubating vertically instead of horizontally is more common, so people expect their eggs to develop vertically.

That said, it appears that you are candling that egg from the pointy end, and the air cell will be on the blunt end. You're not candling from the right side.

New posts New threads Active threads

Top Bottom