But if you are adventuresome, try to hatch some in your dehydrator. Through the years, I have often had to finish hatching chicks or ducklings which, for various reasons, had been abandoned during the last few days of incubation. This year, I used the dehydrator for almost the entire incubation period of three weeks. Three little chicks successfully hatched.
To determine the proper temperature for the dehydrator, I placed a thermometer under a setting hen. (A thermometer is essential!) The mother hen kept her eggs at 100° F. so I tried to maintain an even heat of 98° - 100° F. in the dehydrator.
The area where I had the most trouble was in keeping the moisture just right. I first tried a moist cloth directly under the eggs but this kept the eggs almost wet. Some of the eggs succumbed to my inefficient method; they either dried out or drowned. Next I tried placing a pan of water on a heavy duty tray placed directly under the container of eggs. This seemed to provide the proper amount of moisture.
Two other important procedures had to be remembered.
First, the eggs needed to be turned morning and night. By marking each egg with an "x" on one side and an "o" on the other, it was easy to keep track of the process. I turned the "x"s up in the morning and the "o"s in the evening. Secondly, the eggs had to be cooled once every day. A friend taught me an easy method to determine if the eggs had cooled enough. Hold the egg against your closed eyelid. When it feels neutral (neither warm nor cool) it has cooled enough to return to the dehydrator. (This method is similar to testing the milk for a baby's bottle on your wrist.)
At least once a week I gathered up the eggs to check the growth of the embryos. In a darkened room, I held each egg directly over a flashlight so that the light shown through the egg. At first, weak blood veins and a tiny heart were visible. The next time I checked, the tiny mass had begun to darken. Just before hatching, the egg appeared completely full except for the air space on one end. The eggs needed plenty of moisture at hatching time so the chicks could move easily in the shell.
Once the first peck marks appeared on an egg, it took about a half a day for the chick to hatch. Only rarely is it wise to help the chicks out of the shell -- they need the struggle to gain strength.
A dehydrator tray was home for the baby chicks' first two days. A feather duster "mama" kept them content and secure. Their box was then moved to the top of the dehydrator where they were kept warm and comfortable while they learned about food and water. I taught the chicks to drink by carefully picking them up and dipping their beaks into a jar lid filled with water. They got the hang of it after about two "lessons".
Hatching "my" chicks was a great experience. Although it was very time consuming, I plan to hatch more later this summer.
NOTE: Store bought eggs are never fertile. Find a farm flock with a couple of roosters if you want to try this fun project.