Fertility and Litter Size in Inseminated Nulliparous Gilts with Frozen-Thawed Semen. Technical Note

The aim of this study was to determine the conception rate (TC), the number of piglets born/litter (LNT), the number of piglets born alive/litter (LNV) in 20 gilts Duroc, after post-cervical (IAPC) artificial with frozen-thawed semen (SC). According to the time of expression of oestrus, sows were bred twice with varying intervals of insemination (ITEI) 8 hours (h) (8: 00 a.m. to 4: 00 p.m.) and 16 h (4: 00 p.m. to 8: 00 a.m.) with SC of two Pietrain boars, using 10 straws of 0.5 ml with 600 x 10(6) sperm/straw. In the first IAPC, six straws were used, while in the second, the remaining 4 were used. The statistical analysis was descriptive, using mean +/- standard deviation. The inseminated sows showed a TC 80% (16/20) and results of LNT and LNV per litter corresponded to 5.75 +/- 2.33 and 4.13 +/- 2.08, respectively, noting that the piglets had high body weight at birth fostering difficult births. As expected, the TC using the protocol ITEI 16 h corresponded to 40% (2/5 gilts) while ITEI 8 h provided a TC 93.33% (14/15 gilts). In CONCLUSION, this study confirms that is possible implement the IAPC in gilts and gets good TC with the use of SC and ITEI 8 h, however, the litter size (LNT/LNV) significantly affects at using SC which is recommended only for genetic.