Background: L-carnitine is an important amino acid in sperm metabolism and possesses antioxidant properties. It makes energy easy for spermatozoa to access, which helps in sperm movement, and has the effect of decreasing reactive oxygen species production, which helps in lessening their harmful effects. Aim: To investigate the optimal dose of L-carnitine to be used in bull semen extenders for mitigating the harmful effects of reactive oxygen species during semen cryopreservation. Methods: A total of 38 ejaculates (30-55% motility) were collected and extended using a Tris-yolk-fructose extender. Each sample was divided into five groups: a control and four groups supplemented with L-carnitine (0.03, 0.05, 0.08, and 0.1 mg/ml). Sperm motility, viability, and abnormalities were assessed before and after cryopreservation. Results: Supplementation of the semen extender with L-carnitine for low-motile bull sperm significantly improved sperm motility, with the optimal concentration being 0.05 mg/ml (P<0.05). Additionally, L-carnitine reduced sperm abnormalities and mortality post-thaw. These findings indicate that L-carnitine can be a valuable semen extender supplement to enhance sperm preservation during cryopreservation. Conclusion: Both before and after cryopreservation, certain sperm functional parameters improved following in vitro bull sperm activation with L-carnitine-enriched media.
Ahmed Al-Ebady (Wed,) studied this question.