L-Carnitine supplementation to the stallion semen extender attenuates the cryopreservation induced oxidative stress and ameliorates sperm functional attributes.

OBJECTIVE

The current study evaluated the effect of L-Carnitine supplementation to the stallion semen extender on pre-freeze and post-thaw semen quality and oxidative parameters in Marwari breed stallions.

MATERIALS AND

METHODS

For this purpose, thirty-six semen ejaculates (6 ejaculates from each stallion) were collected using an artificial vagina (AV) from six adult Marwari stallions. The gel free semen was extended with different concentrations of L-Carnitine (LC) i.e. 0 mM (control), 2.5 mM (T1), 5 mM (T2) and 10 mM (T3). Pre-freeze and post-thaw semen evaluations were conducted for various seminal attributes and oxidative parameters.

RESULTS

The results indicated that, all LC supplemented groups (2.5, 5 and 10 mM) exhibited improved progressive motility, acrosome integrity, plasma membrane integrity and mitochondrial membrane potential (MMP) at both pre-freeze and post -thaw stages (P < 0.05) in comparison to the control group. Compared to that in the control, the addition of 5 mM LC induced an increase (P < 0.01) in sperm motility (31.76 ± 2.08 vs 43.87 ± 1.95 %), acrosome integrity (58.56 ± 0.88 vs 66.86 ± 1.11) and MMP (55.66 ± 0.84 vs 65.55 ± 1.15). Antioxidant enzyme levels viz, superoxide dismutase (SOD) and total antioxidant capacity (T-AOC), levels were increased (P < 0.01), glutathione peroxidase (GPX) levels also showed higher values (P < 0.05), exclusively in 5 mM (T2) group and malondialdehyde (MDA) levels decreased (P < 0.05) in the all the LC supplemented groups at post-thaw stage.

CONCLUSION

In conclusion, L-Carnitine supplementation to the stallion semen extender enhanced the semen quality at pre- and post-thaw stages and at 5 mM LC, the oxidative parameters were ameliorated in post- thaw semen of Marwari breed stallions.