2、 How to choose breeding duck eggs
The quality of breeding eggs has a great impact on the hatching rate and the quality of ducklings. It is also one of the keys to the success of the operation of the hatchery, and has a great impact on the survival rate of ducklings and adult birds. The quality of seed eggs is good, the viability of embryos is strong, various nutrients for embryo development are rich, and the hatchability of seed eggs is high. Therefore, strict selection must be made according to the requirements of egg breeding.
（1） Quality requirements for breeding eggs:
1）The source of breeding eggs should first pay attention to the quality of breeding ducks, and select the breeding eggs of ducks with stable genetic performance, good production performance, high fertility and good health.
2） To ensure the freshness of the seed eggs, the shorter the storage time of the seed eggs, the better. The best storage period is 7 days, and 3-5 days. Seed eggs within two weeks can maintain a certain hatching rate. If they are more than two weeks, the hatching period will be delayed, the hatching rate will be reduced, and there will be more weak ducklings. The freshness of seed eggs is not only related to the storage time, but also related to the temperature, humidity and method of storage.
3） The shape, size and shape of the egg should be normal, oval, too long, too round, and pointed at both ends should not be used as seed eggs. The egg weight should meet the requirements of the breed, and it is not good to enlarge too small. The ducklings hatched with too small egg weight are small, and the hatching rate is low if the egg weight is too large. The egg weight of large meat duck is generally 85-95 grams.
4）The structure of eggshell is dense and uniform, the surface is normal, and the thickness is moderate. The eggshell thickness is generally 0.035-0.04 mm. The eggshell is too thick. When it is too thin, it will be heated slowly when it is hatched. The water is not easy to evaporate. The gas exchange is poor. It is difficult to break the eggshell. When it is too thin, the water evaporates too fast, and the hatching rate is reduced. The eggshell structure is uneven and the surface is rough.
5） The cleanliness of the eggshell surface. The eggshell surface should be free of feces, soil and other dirt, otherwise, the pathogenic microorganism in the dirt will invade the egg and cause the seed egg to deteriorate. Or because the dirt blocks the stomata, hinders the gas exchange of the egg and affects the hatching rate. At the same time, the machine is polluted during the incubation process. If a few eggs are slightly polluted, necessary treatment shall be carried out before incubation.
