Comparison of different extenders with defined protein composition for storage of stallion spermatozoa at 5 degrees C.

The research explores the effectiveness of three different semen extenders (EquiPro, EquiPro TM, and AndroMed-E) in maintaining the fertility of stallion spermatozoa during cooled storage. Topline findings indicate that all of them decrease motility over time, with semen diluted in the sterilized form, EquiPro TM, and AndroMed-E losing velocity more rapidly than the dry formula EquiPro.

About the Research

• The research investigates the potency of three different extenders – EquiPro, EquiPro TM, and AndroMed-E – used in conserving the fertility of stallion sperm during storage at 5 degrees Celsius. Extenders are substances added to semen to maintain its viability over prolonged periods.
• The study reveals a decline in total motility (movement) in all extenders over the course of the four-day storage period.

Comparison of the Three Extenders

• EquiPro is an extender that has its protein derived from defined caseinates and whey proteins; it is administered in a dry form which is then diluted in distilled water before usage.
• EquiPro TM mirrors EquiPro in its composition but comes in a pre-sterilized, ready-to-use liquid form.
• AndroMed-E is a third extender that uses soybean lecithin as its protein source.

Difference Between Extendrs and How They Affect Stallion Spermatozoa

• The study found that sperm diluted in liquid form EquiPro TM and AndroMed-E exhibited a faster decrease in velocity than semen diluted in dry form EquiPro.
• Despite EquiPro and EquiPro TM having the same chemical composition, differences were noted in their effect on sperm velocity. The researchers speculated that this discrepancy could result from the heat sterilization process employed in the preparation of EquiPro TM.
• Furthermore, the viability of sperm diluted in AndroMed-E was found to be lowest on the initial day and the fourth day.

Interpretation of Findings

• The findings suggest that although EquiPro and EquiPro TM share the same chemical composition, their formats (dry and pre-sterilized liquid, respectively) result in different occupancy rates, with the liquid form showing accelerated sperm velocity loss.
• The study also suggests that heat sterilization in semen extender production may negatively affect sperm motility, observing such a pattern in the liquid, sterilized extender used – EquiPro TM.
• AndroMed-E, despite being a different extender altogether, also showed early velocity loss and lower overall viability, revealing it may not be as effective as EquiPro in maintaining stallion spermatozoa fertility in cool storage conditions.