INRA96 Supplemented With Phospholipids Liposomes, A Promising Approach for Stallion Sperm Chilling.
Authors: Eterpi Mickael, Magistrini Michele, Couty Isabelle, Gavin-Plagne Lucie, Aguirre-Lavin Tiphaine, Schmitt Eric, Carion Olivier
Journal: Journal of equine veterinary science
Summary
# Editorial Summary Cooled semen technology has become central to equine breeding programmes, yet the standard INRA96 extender fails to adequately protect sperm from some stallions—the so-called "bad coolers"—whose semen deteriorates rapidly during storage at 4°C. Eterpi and colleagues investigated whether supplementing INRA96 with liposomes derived from egg yolk phospholipids could enhance sperm preservation during chilled storage, testing ejaculates from two studs diluted in either conventional INRA96 or the experimental formulation and measuring motility parameters at 24 hours, 72 hours, and up to seven days using computer-assisted semen analysis. The experimental extender substantially outperformed standard INRA96: whilst total and progressive motility declined significantly between day one and day three in the control group (P < 0.05), no meaningful decline occurred in the liposome-supplemented formulation, and both motility measures remained significantly higher in the experimental group at days three, six, and seven across both studs. For practitioners managing difficult-to-chill stallions or requiring extended semen viability for transported doses, this phospholipid liposome approach offers a practical refinement that could expand the use of cooled artificial insemination, potentially reducing the need for fresh semen collection or freezing protocols with their associated complications.
Read the full abstract on PubMed
Practical Takeaways
- •This novel extender formulation could expand the utility of cooled transported semen in studs currently limited by 'bad cooler' stallions, potentially improving breeding management options
- •The protective effect appears sustained through 7 days of storage, suggesting improved flexibility in semen transport and breeding scheduling logistics
- •Further validation with larger sample sizes and fertility trials needed before commercial implementation, but results support advancing this approach through field trials
Key Findings
- •INRA96 supplemented with egg-yolk phospholipid liposomes (EE) prevented significant motility loss between 24-72 hours, whereas standard INRA96 showed significant decline (P < 0.05)
- •Total and progressive motility were maintained at significantly higher levels in EE compared to INRA96 at days 3, 6, and 7 of storage at 4°C
- •Liposome supplementation shows promise as an alternative protective agent for stallions previously considered unsuitable for cooled-semen technology