Detection of DNA Damage in Frozen Bovine Semen Using Eosin Staining

<b>Background and Objective:</b> Early detection of DNA defects in spermatozoa is vital because genetic abnormalities are associated with infertility and miscarriage. Eosin is an acidic stain with negatively charged chromatolytic components also found in the cytoplasm of spermatozoa. This study aimed to observe the effectiveness of eosin staining in detecting spermatozoa DNA deterioration. <b>Materials and Methods:</b> A total of four-hundred frozen beef straws from Simmental, Limousin and Brahman cattle and Ongole crossbreeds, were obtained from the Singosari National Artificial Insemination Center, Malang, Indonesia.Hydrogen peroxide was used to degrade frozen sperm. In addition, the sperm was subjected to three treatments: Agarose trapping, membrane lysis and eosin staining. <b>Results:</b> Damaged bull spermatozoa stained with eosin were bright red in color around the head and mid piece, whereas the head of undamaged spermatozoa were darker red. The average value of damaged DNA was 89.08±3.27% as assessed with eosin staining. <b>Conclusion:</b> Eosin staining effectively detects DNA damage in bull spermatozoa, but extended effectiveness tests are considered necessary.