Evaluation of Sperm DNA Fragmentation using TUNEL Assay in Different Animal Species

Abstract

The studies of spermatozoa DNA fragmentation at the level of different animal species are very limited. This study examined the sperm DNA fragmentation in several animal species (bulls, chickens, and mice) by utilizing terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. This study used a total of 24 different semen samples of Peranakan Ongole (PO bulls) or Ongole grade bull, chickens (KUB Chicken), and mice. Eight semen samples each were collected by three different methods. Semen samples of Peranakan Ongole (PO) bull were collected by artificial vagina method, semen samples of Kampung Unggul Balitnak (KUB) chicken were collected by abdominal massage method, and semen samples of mice were collected by epididymal collection method. Evaluation rate included the motility (%), viability (%) by eosin-nigrosine staining method, membrane integrity (%) by hypo-osmotic swelling test (HOST) method and sperm DNA fragmentation (%) by the TUNEL assay method. The results showed mice had the highest DNA fragmentation rates as compared to others species under study, while bull semen samples showed the lowest rates of DNA fragmentation. Significant differences in mice semen could be affected by the quality of chromatin. The TUNEL method might not effectively interpret the chicken semen samples better than the bulls and mice. However, sperm DNA fragmentation can be used to determine semen quality comprehensively based on the rates of DNA damage.