Alpha-zearalenol negatively influences ram sperm parameters during liquid storage

Abstract

This study was aimed to investigate the effects of 17 𝛽-estradiol (E2) and 𝛼-zearalenol (α-ZOL) on motility parameters, plasma membrane integrity, levels of produced nitric oxide (NO) and total antioxidant capacity of Ghezel ram sperm during the liquid storage at 4 ˚C, for various periods of time. Semen samples were collected from four rams and diluted with Tris–egg yolk extender and supplemented with E2 (100 µmol) or different concentrations of α-ZOL (100 pmol, 100 nmol and 100 µmol) at a final concentration of 200 × 10⁶sperm per mL. We failed to show any significant effect of E2 at 100 µmol concentration on ram's sperm parameters while α-ZOL resulted in a significant decrease of plasma membrane integrity at 100 µmol concentration (55.40% for α-ZOL <em>vs</em> 62.20% for control) after 96 hr incubation. Alpha-ZOL had decreasing effect on sperm motility parameters including curvilinear velocity and average path velocity at 100 µmol concentration after 96 hr storage. Although remarkable reduction of total antioxidant capacity at high concentration of α-ZOL and long incubation time was found, however no significant changes were recorded in NO level during storage time. It was concluded that the detrimental effect of α-ZOL on ram sperm might be attributed to its induced oxidative stress and damage to the plasma membrane.