"If it doesn't kill you it makes you stronger". Sublethal stress can improve gamete quality. In this research we will investigate the peroxiredoxins (PRDXs) expression in bull spermatozoa after H2O2 exposure and their role in sperm-oocytes interaction. Moreover, we will evaluate the expression pattern of PRDX6 in oocytes of different quality (small, medium and large oocytes, based on oocyte diameter) and its role in repairing oxidative sperm DNA damage and subsequent in vitro embryo production.