To know if the egg is a winner look for a network of blood vessels that appear white. A dark outline at the center of the blood vessels is the embryo. You may even see the dark eyes of the embryo or the embryo moving slightly. These are both telltale signs that the egg is a winner.
If you are not sure whether the embryo is alive, place the egg back in the incubator and retest later. A second test can be made after 14 to 16 days of incubation. If the embryo is living, only one or two small light spaces filled with blood vessels can be seen, and the chick may be observed moving.
* During the last 3 days of a hatch, it is best to avoid candling the eggs unless you have a specific reason to. * A vague ring inside the egg and little or no veins. * After 10 days the egg is still clear.
Does moving the egg during candling damage it? No, as long as you're careful and as long as you don't candle after day 18 of incubation. You will generally need to turn the egg to see what's going on inside, particularly as you come to the later stages of incubation. Always take it slowly.
If chick embryos develop to the pipping stage, or at first shell cracking at hatching, they are normally healthy enough to hatch unless some incubator adjustment prevents it from happening. The problem is usually caused by either 1) poor ventilation or 2) improper humidity.
You'll see blood pumping through the heart of a tiny, developing embryo if you candle a fertile egg on Day 4. If the embryo dies at this point, you may still see a faint network of blood vessels inside the egg's contents. An embryo dying at this point will show a large, black eye.
Quitters — When embryos stop growing, we call them "quitters." You will see a thin, blood ring around the yolk. Quitters are removed from the incubator and thrown away. If you want to view the embryo, have your parent or teacher help you open the egg. Be sure to wash your hands afterwards.
Do fertile eggs sink or float? Eggs sinking or floating is nothing to do with fertility – it's to do with freshness. The older an egg is, the more it will float. So a fresh egg will sink; the more it tilts upwards or even floats, the older it is.
Chicks will typically hatch at day 21. If the fertilized eggs were cooled prior to incubation, the process might take a little longer. If you are at day 21 with no hatch, give the eggs a few more days. When the big day comes, let the chick hatch on its own.
Step 5: Lockdown, Days 18-20
On day 18 of the incubation period, you should stop turning the eggs by hand or turn off and remove eggs from the automatic turner. The chicks are nearly fully developed and they will position themselves inside the egg to prepare for hatching.
Slightly rotating the egg will allow you a good view into the egg. Candling eggs that have light-colored shells are easier than eggs with dark-colored shells. When candling an egg, you will be able to see the egg air cell and the egg yolk. The egg yolk will look like a fuzzy, darker blob in the center of the egg.
Around day 20, as the chick prepares to hatch, you will be able to hear chirps from inside the egg. If you candle at this point, you will be able to see the chick's head poking up into the air cell. This indicates that the chick is preparing to hatch. White eggs are easiest to see into when candling.
Candling eggs through the air cell and around its low point at the front will show very little visible detail. The dense yolk sac appears as a dark mass, though the major umbilical vessels may be seen.
And candling does not harm your eggs. Just as the mother would naturally leave the nest for a short time each day, you can safely take your incubating eggs out of the incubator for the few times you will be candling them.
Incubating, days 4 and 5.
If you're fortunate enough to have light-shelled eggs, from about day 5 you'll start to see tiny spider like markings appearing in the yolk area when you candle your eggs. In a dark-coloured egg like the Marans or Welsummer, they're much more difficult to spot.
Day 21 is the most common time for hatching, but if your eggs are showing no signs of pipping yet please, do not worry. Chicks can develop at different speeds and incubation times are affected by many variables including temperature variations. I've had chicks hatch as late as day 26. So don't give up too soon!
Biologists determine a pipped egg as one where the turtle has cut through the shell, but still remains inside the egg. When an egg is pipped, the sea turtle pops it open with a sharp, temporary tooth called the caruncle. The turtle will continue to cut through the shell, and the fluids will drain from the eggs.
It's likely that the chick will just hatch a little later. I have had chicks hatch as late as day 26, so don't despair. And do not be tempted to "help" the chick out of the egg.
First candling: 7 days
Sometimes, it's hard to see the embryo, and it might be in the centre or opposite side of the egg. Rotate the egg until you get the best view. If you're still not seeing it clearly, then it's best to wait another day or two before trying again.
While I can expect to hear cheeping from within the eggs at any time now, it is most commonly heard around day 20. Chicks can hatch earlier or later than day 21 depending on whether temperatures were off a little bit one way or the other (too cool and they'll hatch later, too warm and they'll hatch earlier).