Lactoferrin increases sperm membrane functionality of frozen equine semen

Area of Science:

• Veterinary Science
• Reproductive Biology
• Biochemistry

Background:

• Cryopreservation of equine sperm increases reactive oxygen species (ROS) generation, potentially damaging sperm quality.
• Antioxidants are crucial for mitigating oxidative stress during sperm cryopreservation.

Purpose of the Study:

• To evaluate the efficacy of lactoferrin (Lf) and catalase (Cat) as antioxidants in improving the quality of frozen-thawed equine sperm.
• To determine the protective effects of Lf and Cat on sperm motility, membrane integrity, and acrosome status.

Main Methods:

• Semen from six stallions was cryopreserved using extenders with either no antioxidant (control), Lf (500 μg/ml), or Cat (200 IU/ml).
• Post-thaw sperm quality was assessed using computer-assisted sperm analysis (CASA), hypoosmotic swelling test (HOST), and epifluorescent microscopy.
• Concentrations of nitrite, hydroperoxide, and iron were measured spectrophotometrically.

Main Results:

• Sperm treated with Lf exhibited a significantly higher percentage of functional membrane sperm (50.7%) compared to the control (37.6%).
• Lf treatment resulted in lower concentrations of iron and nitrite in frozen semen compared to the control.
• Catalase (Cat) did not show significant improvements in the evaluated parameters compared to the control.

Conclusions:

• Lactoferrin (Lf) demonstrates a protective effect on stallion spermatozoa during cryopreservation.
• Lf supplementation in freezing extenders enhances sperm membrane functionality and reduces lipid oxidative agents, improving post-thaw quality.