L-carnitine added to post-thawed semen acts as an antioxidant and a stimulator of equine sperm metabolism.

The research studied the effect of adding l-carnitine (LC) to thawed horse sperm samples, finding that LC acted as an antioxidant and improves sperm metabolism, thus increasing fertility rates.

Objective of the Study

• The main objective of this study was to improve the in vitro (test tube or lab environment) sperm quality and in vivo (within a living organism) fertility of thawed horse semen by adding LC post-thawing process. The researchers tried different concentrations of LC to find out which one delivered the best results.

Methodology

• This study performed in vitro experiments testing four different treatments of semen samples – a control (without LC) and samples with 0.5, 1, and 2 mM LC added respectively.
• The researchers checked the sperm’s motility (movement ability) and kinematics (study of motion), membrane integrity and internal calcium ion concentration (symbolized as [Ca]).
• To gauge the antioxidant bioactivity of LC, they measured hydrogen peroxide and nitrite concentrations (NO).
• The study also examined the fertility rate through the artificial insemination of mares (female horses).

Results

• The treatment with 1 mM LC showed promising results, elevating the sperm’s internal calcium ion concentration, reducing nitrite concentration, and increasing sperm straightness percentage – indicative of enhanced sperm health.
• Most importantly, this treatment led to a higher pregnancy rate when compared with the control group.
• The results thus suggest that the addition of 1mM LC can act as an antioxidant and stimulate sperm metabolism in thawed horse semen, increasing their fertility rate.

Conclusions

• The positive impacts of LC highlight it as a potential alternative for enhancing the fertility of poor quality, thawed equine semen.
• This discovery presents potential to boost fertility rates in the horse breeding industry and needs further research to strengthen these findings.