Intra-uterine and deep intra-uterine insemination using cryopreserved boar semen in spontaneously-ovulating sows

Abstract

The present study was performed to investigate the in vivo fertility of frozen-thawed (FT) boar semen after intra-uterine (IUI) and deep intra-uterine insemination (DIUI) in spontaneously-ovulating sows. A total of 48 weaned sows were included. The sows were divided into three groups, i.e. natural mating (NM) (n=30), IUI (n=9) and DIUI (n=9). In the IUI and DIUI groups, the sows were inseminated twice, at 24 and 36 h after the detection of oestrous by IUI with 2 × 109 spermatozoa/dose or DIUI with 1 × 109 spermatozoa/dose. Transrectal ultrasonography was used to determine the time of ovulation after insemination. The results revealed that the conception as determined by a 24-day non-return rate of the sows was 96.6%, 88.8% and 66.6% (p=0.03) and the farrowing rate (FR) was 96.6%, 66.6% and 66.6% (p=0.01) in NM, IUI and DIUI groups, respectively. The numbers of total piglets born per litter were 9.4±2.8, 11.3±2.9 and 7.6±3.1 piglets in the NM, IUI and DIUI groups, respectively (p=0.10). These data indicate that the spontaneously-ovulating weaned sows inseminated with either IUI or DIUI using a relatively low numbers of FT spermatozoa resulted in a lower FR compared to NM. The total number of piglets born per litter after IUI was higher than DIUI.