impact of reactive oxygen species on spermatozoa: abalancing act between beneficial and detrimental effects

reactive oxygen species (ros)plays an important role in sperm motility. the physiological generation at low concentration induces beneficial effects on sperm functions and plays a significant role in sperm metabolism. meanwhile, the excessive generation of reactive oxygen species can overwhelm protective mechanism and triggers changes in lipid and protein layers of sperm plasma membrane, which induces lipid damage, protein damage, dna damage, motility impairment and alteration in capacitation and acrosome reaction. reactive oxygen species (ros) can be measured by variable biomarkers as melondialdehyde (mda) concentration, individual free radicals, etc. the quantification of free radicalsin livestock semen is also briefly reported.