l-carnitine enhances the kinematics and protects the sperm membranes of chilled and frozen-thawed Peruvian Paso horse spermatozoa.

The research article investigates how l-carnitine supplementation in skimmed milk-based extenders improves survival and functionality of chilled and frozen-thawed spermatozoa in Peruvian Paso horses.

Objective of the Research

• The paper’s main objective is to investigate the impact of l-carnitine (LC) supplementation in two different skimmed milk-based extenders (INRA-96® and UHT) on the survivability and functionality of chilled and frozen-thawed Peruvian Paso horse sperm.

Methodology of the Research

• An initial experiment was conducted to determine the optimal LC concentration among various options (0, 1, 5, 10, 25, and 50 mM).
• Nine ejaculates from three stallions, chilled for up to 96 hours, were used to perform this test.
• The research then examined the impact of 25 mM LC supplementation on chilling (with INRA-96) and freezing (with INRA-Freeze®) using pooled samples from sixteen ejaculates from four stallions. Each pool consisted of two ejaculates.

Results of the Research

• Results demonstrated that all LC concentrations significantly improved kinematic variables (total and progressive motilities, curvilinear and straight-line velocity, and beat-cross frequency), and the integrity of plasma/acrosome membranes compared to non-supplemented chilled sperm samples.
• The use of 25 mM LC was found to be more effective than lower LC concentrations (1-10 mM) in preserving post-chilled values of velocity, beat-cross frequency, and plasma/acrosome membrane integrity in the long term.
• Additionally, post-thaw values of total motility, the amplitude of lateral head displacement, and plasma/acrosome membrane integrity were significantly better when 25 mM LC-supplemented INRA-Freeze® extender was used.

Conclusion of the Research

• The research concludes that using l-carnitine in skimmed milk-based extenders significantly enhances kinematic variables and protects membrane integrity, enhancing the archive potential of chilled and frozen-thawed Peruvian Paso horse spermatozoa.