Intracellular hydrogen peroxide’s effect on quality parameters of rooster sperm in freeze/thaw cycle

Relevance . One of the factors decreasing total motility after cryopreservation rooster’s sperm is influence of reactive oxygen species. Morphological and biochemical features of avian spermatozoa structure, which make them more susceptible to cryopreservation process compared to mammalian spermatozoa, may also be the reason why avian spermatozoa are more susceptible to oxidative stress. Methods . The purpose of the study is to trace the change in the level of intracellular reactive oxygen species, in particular hydrogen peroxide (H 2 O 2 ), during the cryopreservation of rooster sperm, to assess its effect on the quality and viability of sperm. Results . A negative correlation (r = -0.68, p < 0.05) was found between the intracellular level of hydrogen peroxide and the number of dead cells in native sperm. In the frozen (thawed) seed, a weak relationship was observed between these indicators (r = -0.10). There was a significant effect of the level of intracellular hydrogen peroxide in freshly obtained ejaculates on the overall mobility of frozen (thawed) semen (r = -0.65, p < 0.05). This allows us to assume that, similarly to mammalian spermatozoa, the production by cells of an increased amount of reactive oxygen species (H 2 O 2 ) in the freezing (thawing) cycle negatively affects the functional status of mitochondria, which, as is known, are the main source of energy for the sperm, ensuring the operation of the kinetic apparatus of the sperm and its general mobility. Data were obtained on the individual variability of the hydrogen peroxide content in the sperm of roosters at the age of 61 weeks in the freezing (thawing) cycle, allowing the selection of roosters according to this indicator