What are the different methods used in hatching chicken eggs?
One method is called incubation, and includes two main types: natural and artificial.
With natural incubation, the broody hen sits on the eggs all day long for 21 days to incubate them until they hatch. She maintains a temperature of 100 degrees Fahrenheit, needed to ensure the proper embryonic development of the eggs. To keep the eggs at the correct humidity she splashes water on them from her beak. This is why you need to provide her with easy access to water.
The broody hen also plucks her breast feathers so the eggs can touch her skin. She also talks to the chicks through their shells to imprint her voice, so they will know who their mama is when they hatch.
Artificial incubation uses an incubator instead of a broody hen. The machine provides the correct controlled environment for the developing chicks. There are many commercial artificial incubators of varying capacities available. Most use electricity, but some use gas or kerosene for heating.
Your artificial incubator should be set up and running at least 24 hours before loading the eggs inside. This will allow the environment inside the incubator to reach the necessary temperature and humidity levels. The countdown to 21 days begins after you load the eggs into the incubator. Then, you need to make sure the temperature and humidity levels are correct.
Eggshells are porous, allowing oxygen to enter and carbon dioxide to exit. Adequate ventilation is necessary to provide the embryo with oxygen so the chicks can breathe.
The position of the eggs in the incubator can also influence the hatch rates. For best results, the eggs should be placed with the pointed ends down and turned regularly by hand at least three times a day until day 18.
Candling is done as early as day 7 of incubation, which means looking at the inside of the egg by shining a light through the shell. This is done to determine if the egg is fertile and detect defects in eggshells and embryonic development. You can do this with a flashlight or spot candler. Just don’t candle the eggs all at once. Candle only a few at a time and don’t keep the egg out of the incubator for more than 5-10 minutes.
By day 18 you may observe the eggs shifting about on their own, which means the chicks have formed. A chick will peck a small hole in the large end of the egg to take its first breath. Once the chick is free from the egg, leave it to dry off in the incubator for three days. Then move them to the brooder box for their first weeks of life.