The incubation process refers to the process that the fertilized eggs of poultry develop into new individuals outside the mother. Natural hatching is the spontaneous hatching behavior of females after laying eggs; Artificial incubation is controlled manually by certain equipment, and is the main incubation method of modern poultry industry. Each modern large incubator can incubate 10000 to 100000, and its temperature, humidity, egg rotation and ventilation can be automatically controlled. The incubation period of poultry varies with bird species: 21 days for chickens, 28 days for ducks, 30 to 33 days for geese, 18 days for pigeons, and 17 to 18 days for quails. The suitable incubation temperature for various poultry is different. If the chicken's 37.8 ℃ is taken as the benchmark, the duck, goose and turkey will be reduced by about 0.3 ℃. The temperature of hatching period can be reduced by 0.5 ℃. The relative humidity of hatching should be controlled within 40% - 70%, 53% - 60% and 65% - 70% during hatching. During the incubation process, especially in the later stage of incubation, good ventilation conditions should be created to facilitate the embryo to continuously absorb oxygen, discharge carbon dioxide and water vapor through the eggshell. In order to make the incubated eggs evenly heated, they need to be rotated regularly, 8 to 12 times a day. The traditional incubation technology also needs to cool eggs. Modern incubators rely on ventilation and cooling systems to control temperature, and do not need to cool eggs. The hatching effect of poultry is measured by fertilization rate and hatching rate. The percentage of the number of fertilized eggs in the number of hatched eggs is the fertilization rate; The percentage of hatching hatchlings to hatching eggs (or hatching fertilized eggs) is the hatching rate, also known as hatching rate and hatching rate. The hatching rate reaches 85%, which is a high level. The good hatching effect depends not only on the hatching conditions, but also on the quality of the seed eggs or the storage time.