Zinc Oxide Nanoparticles Have Beneficial Effect on Frozen‐Thawed Spermatozoa of Holstein Bulls

The aim of this study was to investigate the effect of zinc (Zn) oxide nanoparticles (ZnONPs) on bovine sperm quality after cryopreservation. Semen samples were collected from four healthy, mature Holstein bulls twice a week. The samples with critical quality were then pooled and assigned into four different groups including different concentrations of ZnONPs (0, 0.1, 1.0 and-10 μg/mL of extender). The samples were frozen by using a semi-automatic device and kept until the evaluation. After thawing, total (TM) and progressive -motility (PM), membrane integrity and functionality, acrosome integrity, DNA fragmentation and malondialdehyde (MDA) concentration were assessed. The different concentrations of ZnONPs did not significantly affect TM and PM of bull spermatozoa, when compared to the control (P≥0.05). The percent-age of fast- moving spermatozoa was higher in the treatment supplemented either with 0.1 or 1.0 μg ZnONPs in comparison with the control (P<0.05). Moreover, the results indicated that membrane integrity and functionality and also acrosome integrity of the group treated with 1 μg/mL ZnONP1- was significantly higher than control (P<0.05), while, the percentage of sperm with damaged DNA and MDA concentration was significantly lower in ZnONP1 in comparison with the control (P<0.05). In conclusion, adding 1 μg/mL ZnONP to semen extender, could improve post-thaw bull spermatozoa quality.