Prolonged incubation of frozen-thawed equine spermatozoa for in vitro fertilization: A preliminary study using low temperature and INRA96 medium.

The research attempts to develop a method for keeping frozen-thawed horse sperm viable during in vitro fertilization, specifically using a prolonged 22-hour incubation in the presence of certain compounds at different temperatures and media. They found that the optimal conditions were using INRA96 medium at 30°C, which maintained sperm motility, viability, and acrosome integrity.

Research Purpose

• The aim of this study was to develop a new protocol that would maintain key quality parameters in frozen-thawed equine spermatozoa during a prolonged incubation period. The researchers were specifically interested in the effects of different incubation temperatures and media on the sperm.

Methodology

• The researchers thawed and incubated twelve frozen ejaculates from four stallions in either FERT-TALP or INRA96 media. These media contained compounds known as PHE (penicillamine, hypotaurine, and epinephrine).
• They then incubated these samples at two different temperatures, 30°C and 38.2°C, for 22 hours.
• The team evaluated the total motility, progressive motility, viability and acrosome integrity of the sperm after incubation.

Findings

• The researchers found that the total motility of the sperm was significantly higher when incubated at 30°C in both types of media.
• For progressive motility, the best results were achieved with INRA96 medium at 30°C, compared to 38°C.
• The study also found that sperm incubated in INRA96 medium at 30°C had higher viability and acrosome integrity compared to the other experimental groups.

Conclusion

• The preliminary results suggest that incubating thawed equine sperm at 30°C in INRA96 media with PHE successfully maintains the motility, viability and acrosome integrity of equine sperm. These are important factors for successful in vitro fertilization.
• The findings indicate the potential use of this method for conventional equine IVF, though further research is necessary to confirm the full effectiveness and applicability of the procedure.