Comparison of Single, Fixed-Time Artificial Insemination in Gilts Using Two Different Protocols to Synchronize Ovulation.
Authors: Rodrigues Lima, Amezcua Rocio, Cassar Glen, O'Sullivan Terri L, Friendship Robert
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary Synchronising ovulation in breeding gilts enables fixed-time artificial insemination (FTAI) without the need for oestrus detection, potentially offering producers greater predictability and batch uniformity. Researchers compared two hormone-based FTAI protocols against conventional oestrus-detection breeding in 180 gilts following altrenogest withdrawal: one combining equine chorionic gonadotropin and porcine luteinising hormone (LUT protocol), another using an intravaginal gonadotropin-releasing hormone agonist (TRI protocol), and a control group bred on observed oestrous signs. Both synchronisation protocols substantially compressed farrowing intervals (LUT: 2.4 ± 1.6 days; TRI: 2.9 ± 1.2 days versus control: 4.5 ± 3.3 days), with offspring demonstrating significant weaning weight advantages of 80 g and 64 g respectively when birth weight was accounted for. These findings suggest FTAI protocols could meaningfully improve production efficiency by concentrating farrowings and potentially enhancing piglet performance through better nutritional uniformity, though the authors acknowledge that farrowing rates and litter sizes require optimisation before widespread adoption. For gilt producers managing multiple breeding batches, these synchronisation approaches merit consideration as part of strategic breeding programmes, particularly where labour availability for oestrus detection is limited or batch consistency is a priority.
Read the full abstract on PubMed
Practical Takeaways
- •FTAI protocols using gonadotropin and GnRH agonist treatments can significantly compress farrowing windows (2-3 days vs 4-5 days), improving batch management and resource allocation for pig producers
- •Heavier piglets at weaning with FTAI protocols suggest improved nutritional outcomes; producers should consider these systems for more uniform piglet development and reduced cross-suckling issues
- •While FTAI improves synchronization, current protocols may need refinement to maintain optimal farrowing rates and litter sizes—consult with reproductive specialists before full-scale implementation
Key Findings
- •LUT and TRI protocol gilts farrowed more synchronously (2.4±1.6 and 2.9±1.2 days) compared to control estrus-detection gilts (4.5±3.3 days)
- •Piglets from LUT protocol were 80g heavier at weaning (p<0.001) and TRI piglets were 64g heavier (p<0.05) compared to control, when controlling for birth weight
- •Fixed-time AI protocols improved predictability of gilt breeding timing and farrowing batch uniformity
- •Protocol modifications may be needed to optimize farrowing rates and litter size in FTAI systems