Role of triptorelin and single fixed-time artificial insemination on productive and reproductive performance of hyperprolific sows

Single fixed-time artificial insemination (SFTAI) provides a streamlined approach to improving reproductive management. We evaluated the impact of incorporating triptorelin acetate (GnRH agonist) into a SFTAI protocol on a commercial farm. Hyperprolific sows not in estrus by day 4 post-weaning were randomly assigned to two groups. Group-1 (G1; <i>n</i> = 243) received no triptorelin treatment and daily post-cervical artificial inseminations (PCAI) based on estrus detection (2.59±0.034 inseminations/sow). Group-2 (G2; <i>n</i> = 249) received a single intravaginal dose of triptorelin (0.2 mg) at 96 ± 2 h post-weaning, then one PCAI 22 ± 2 h later. No significant differences (<i>P</i> > 0.05) between groups in conception rate (G1: 98.8 %; G2: 97.6 %), farrowing rate (G1:95.1 %; G2: 94.4 %) or litter characteristics (total born, live-, stillborn and mummified piglets). Both groups showed similar delivery batch durations (<i>P</i> = 0.414). Distribution of deliveries during the delivery period was similar (<i>P</i> = 0.455). Induction of labor was need more frequently in G1 (<i>P</i> < 0.001). G2 had a higher proportion of sows with shorter gestations (112-115 days: 166/235, 70.6 %) compared to G1 (112-115 days: 82/231; 35.5 %, <i>P</i> < 0.001). A significantly higher proportion of G2 piglets received longer lactation (27 - 33 days) compared to G1 (2210/3023=73.1 % vs 2774/4395=63.1 %; <i>P</i> = 0.032). G1 had a higher proportion of low-weight piglets (≤4.0 kg; 716/43950= 16.3 % vs.435/3023= 14.4 %; while G2 had more heavy piglets (≥6.5 kg; 1228/3023=40.5 % vs.1675/4395= 38.1 %) (<i>P</i> = 0.027). Observed differences in lactation length could be responsible for these weaning weight differences, rather than triptorelin treatment itself. This protocol did not worsen productive and reproductive performances.