While pondering if the chicken or the egg came first, for many poultry enthusiasts, the chicken came first when the day-old chicks first arrived in the mail. That's certainly not the only way to obtain your first flock. For folks who are concerned about receiving live animals in the mail, or do not need the minimum number of chicks required by most hatcheries, incubating fertile eggs is another alternative. Incubating eggs is a perfect way to increase your flock size, or provide replacements for birds as needed. Even though hatching fertile eggs is not difficult, you can increase your success rate by following a few guidelines.
Eggs need to be in a specific environment to develop properly and hatch with success. Above all else, the most important feature is temperature – chicken eggs should be incubated between 99 and 102 degrees Fahrenheit, with 99.5 considered to be ideal. Relative humidity should be between 50 to 65 percent, with 55 percent considered to be ideal. To assist proper aeration and gas exchange from the embryo inside the egg and the outside world, the eggs should not be kept in a tightly sealed container.
Usually, chicken eggs hatch after incubating for 21 days. This is an approximation and not an absolute number. During the final three days of incubation, ideally the temperature should be slightly cooler (98.5 degrees) and more humid (65 percent or greater relative humidity) to facilitate successful hatching. The cooler temperature helps account for extra heat produced by the larger embryos and the increased humidity helps the little chicks from getting stuck to the membrane inside the egg shell.
Eggs also need to be moved around regularly for best hatching success. Moving an egg helps to exercise the embryo and helps to prevent it from sticking to the shell. Usually, eggs should be incubated with the pointed end down and air cell up, but it is helpful to turn and tip the eggs back and forth at least twice daily – the more times they are turned, the better. During the hatching phase, it's best for eggs to lay on their sides.
Of course, incubating and hatching eggs sounds like a lot of work. An easier way is to have a broody hen do it for you. A broody hen will sit on eggs to hatch them and brood the chicks. She not only will do the ventilating and warming of the eggs, she will handle the turning and chick-rearing duties to boot.
If you already have a broody hen, she will incubate her own eggs or other fertile eggs obtained elsewhere. Some people try to prevent their laying hens from going broody when they no longer lay eggs – but if you want a few chicks, a broody hen can be a huge help in reaching your goal.