Sows ovulate 24-36 hours after estrus, with an average of 365,438+0 hours. The time for eggs to maintain fertility in the reproductive tract is 8-65,438+02 hours, while the survival time of sperm is 25-30 hours. Therefore, sperm should arrive at the fertilization site 2-3 hours before ovulation. According to this calculation, the suitable mating time is 265,438+0 hours after sow estrus begins. In order to increase the litter size and reduce the litter rate, it is suggested to breed in estrus twice with an interval of 8 ~ 12 hours.

breeding method

1. Single mating

It is a sow in estrus mating with a boar. Its advantage is that the number of boars used is small, but the conception rate and litter size are slightly lower than those of repeated mating.

2. Duplicate matching

A sow is bred with a boar in estrus, and the second time with the same boar, the interval is 12 ~ 18 hours. This breeding method ensures that there are enough capacitated sperm in the fallopian tube during the best fertilization period of the egg, and its conception rate and litter size can be guaranteed, and it is easy to record the parent-child relationship of offspring.

3. Double matching

It is that a sow mates with two boars every 15 ~ 20 minutes in a mating period. The advantage of this breeding method is to increase the choice of eggs and the chances of fertilization with sperm from different genetic backgrounds. Therefore, it is helpful to improve the fertilization rate of sow eggs.

4. Multiple breeding

Estrus once every 12- 18 hours to breed a sow until the sow has no standing reflex in front of the boar. This breeding method has a large workload and a large demand for boars. This method is helpful to improve the conception rate of sows when they are immature in estrus.