Evaluation of bovine sperm telomere length and association with semen quality

Theriogenology. 2020 Dec;158:227-232. doi: 10.1016/j.theriogenology.2020.09.019. Epub 2020 Sep 15.


The study aimed to evaluate if the sperm telomere length can be considered as a new biomarker for sperm quality in bulls. Sperm Telomere Length was evaluated by Monochrome Multiplex Quantitative PCR in group A (n = 8) and group B (n = 8) bulls, classified according to standard semen analysis. Also, this parameter was measured before and after Percoll gradient separation within bulls that produced semen of satisfactory quality. Sperm telomere length, measured as T/S ratio (average ratio of telomere repeats copy number to a single copy gene), was higher in group A than in group B bulls (0.77 ± 0.03 vs 0.43 ± 0.06; P < 0.01). Sperm telomere length was positively correlated with motility, viability and membrane integrity, and it was negatively correlated with sperm anomalies. Furthermore, Percoll gradient selected sperms with higher T/S ratio than unselected sperms (1.19 ± 0.02 vs 0.67 ± 0.03). These results suggest that sperm telomere length can be used as a new marker of bovine semen quality.

Keywords: Bull; Percoll density gradient; Sperm quality; Sperm telomere length; Standard semen analysis.

MeSH terms

  • Animals
  • Cattle / genetics
  • Male
  • Semen
  • Semen Analysis* / veterinary
  • Semen Preservation* / veterinary
  • Sperm Motility
  • Spermatozoa
  • Telomere / genetics