When is the most suitable time to breed a sow after she comes into estrus?

It is most suitable to breed a sow 19 to 30 hours after the start of estrus, or, if you press down on the sow's back with your hand and she stands still, mating 15 to 20 hours afterward gives the highest conception rate. A commonly used method is: when the sow is in estrus, press down firmly on the sow's hindquarters with both hands; if the sow stands still, moves her tail to one side, exposes the vulva and spreads her hind legs as if preparing to bear the pressure, that is the best breeding moment.