Abstract: Due to the limited application of frozen semen in pig farms, the industry lacks large-scale data on the insemination effect of frozen semen, which restricts the promotion of frozen semen. In this study, frozen semen and fresh semen were used for insemination of Yorkshire sows that were in estrus in the same batch. Specifically, 195 sows were inseminated with fresh semen, and 203 sows were inseminated with frozen semen. Data such as the parity, insemination season, total number born, total number born alive, and stillbirths were recorded to compare the insemination effects between frozen semen and fresh semen. The results showed that the farrowing rate of frozen semen insemination sows in autumn was higher than that of fresh semen insemination sows. The total number born from insemination sows with frozen semen was 0.8 piglets less than that from insemination sows with fresh semen. However, in summer, the total number born and the total number born alive from insemination sows with frozen semen were both 0.4 piglets more than those from insemination sows with fresh semen. This research provided a new application scenario for the promotion of frozen semen in pigs.

Key words: Yorkshire pig, insemination, frozen semen, fresh semen, artificial insemination, farrowing rate, total litter size