2. Disinfection: Disinfection of breeding eggs is very important, and the hatching rate of sterilized breeding eggs can be significantly improved than that of non-disinfected breeding eggs. Sterilization of breeding eggs-generally adopts formaldehyde gas fumigation disinfection method, with the dosage of 15g of potassium permanganate and 3ml of fokkoman per cubic meter of space, and fumigation for 2min at the temperature of 27℃ ~ 3℃, which can kill pathogenic microorganisms, especially for viruses and mycoplasmas, and disinfection is generally carried out in a sealed disinfection cabinet.
3. Temperature: Temperature is the first condition needed for hatching. Only at a proper temperature can the embryo undergo normal material metabolism and growth, and the temperature during the incubation period is relatively stable, and its variation range is allowed to be .5 degrees Celsius, and the temperature in the incubation site is uniform, otherwise it is difficult to hatch good results. The incubation temperature is high in the early stage, flat in the middle stage, slightly lower in the late stage and slightly higher in the hatching period according to the embryo development. The temperature is: the eggs are preheated for 6-8 hours before hatching, and the egg temperature is 36-38 degrees Celsius. 1 ~ 7 days, 38.8 ~ 39.2 degrees Celsius, 8 ~ 14 days, 38.5 ~ 38.8 degrees Celsius, 15 ~ 2 days, 38 ~ 38.5 degrees Celsius, 21 ~ 24 days, 38.5 ~ 39 degrees Celsius, with this temperature, the embryo develops normally, and the allantois is is in the small size on 14 ~ 15 days.
4. Humidity: Humidity is also an important condition for the incubation period of wild eggs. If the humidity is insufficient, it will cause the embryo to stick to the shell, and it will be difficult to hatch or the hatched chicken will be light in weight, and the scales on the feet of the chick will be rough and dry. If the humidity is too high, the hatched chick will be heavy, but its egg yolk will be poorly absorbed, its abdomen will be big, its physique will be poor and it will die easily, resulting in a decline in survival rate. In the incubation period, the humidity of wild eggs should be high at both ends, preferably flat in the middle. The high humidity in the early stage can make the breeding eggs heated well and evenly, and it is flat in the middle stage, which is beneficial to the metabolism of embryos. In the late hatching stage, the humidity is increased to dissipate excessive physiological heat, make the eggshell structure loose, and facilitate pecking and hatching. The humidity in the early stage is 6% ~ 65%, in the middle stage it is 55% ~ 6%, and in the late stage it is 6%.
5. egg turning: egg turning can promote embryo activity, prevent the contents from adhering to the eggshell, and make the incubation period heated evenly. Practice has proved that the egg can be turned once every 8 hours for 1 ~ 2 days, and the turning angle is 18 degrees. If the egg is not turned during the hatching period for 21 ~ 24 days, only the side-centered egg can be adjusted, which can meet the requirements of embryo egg development and the hatching effect is ideal.
6. Oven drying: In the middle and late period of incubation, the temperature of the egg can reach 38.8 degrees Celsius, the surface area of the eggshell is relatively small, the pores are small, and the heat dissipation is slow. During this period, the air exchange of the embryo can be enhanced, and the accumulated heat in the egg can be eliminated. After 16 days of incubation, the egg should be dried once a day for 2-24 days, with much physiological heat, twice a day, and the length of the egg drying can vary according to the situation.
7. water spraying: water spraying is one of the keys to improve the hatchability. Water spraying has three functions:-destroying the membrane on the shell; (12) promoting the contraction and expansion of eggshell and shell membrane respectively, destroying their integrity, increasing permeability, accelerating water evaporation and normal weightlessness of eggs, making the air chamber larger and providing sufficient oxygen; and (3) causing eggshell to be brittle. When the thickness of the shell of wild eggs is reduced to 35 degrees Celsius, they will continue to hatch. The shell is hard, the former affects the evaporation of gas and water, and the latter hinders the pecking of the shell. The existence of membrane on the shell is beneficial to the first few days of incubation. With the continuous increase of embryo age, especially when the allantois is closed, it needs to inhale more oxygen and discharge a lot of metabolites, which will have an adverse effect on the development of the embryo. Therefore, it is necessary to spray warm water of 31 ~ 38 degrees Celsius on the embryo eggs of 21 ~ 24 days (not too early or too late) Under the action of repeatedly drying eggs and spraying water, the eggshell becomes brittle from hard, and chicks are easy to break their shells, reducing the stillbirth in the early stage.