Nuclear DNA Fragmentation in Boar Spermatozoa: Measurement Methods and Reproductive Performance Implications

Raquel Ausejo; Juan Manuel Martínez; Noelia Mendoza; Alfonso Bolarin; M Teresa Tejedor; Maria Victoria Falceto

doi:10.3389/fvets.2022.929858

Nuclear DNA Fragmentation in Boar Spermatozoa: Measurement Methods and Reproductive Performance Implications

Front Vet Sci. 2022 Jun 30:9:929858. doi: 10.3389/fvets.2022.929858. eCollection 2022.

Authors

Raquel Ausejo^{1

2}, Juan Manuel Martínez³, Noelia Mendoza², Alfonso Bolarin¹, M Teresa Tejedor⁴, Maria Victoria Falceto¹

Affiliations

¹ Department of Animal Pathology, Obstetrics and Reproduction, Faculty of Veterinary Medicine, University of Zaragoza, Zaragoza, Spain.
² Department of Biotechnology R&D, Magapor S.L., Ejea de los Caballeros, Spain.
³ Department of Research and Development, CiencIAnova Magapor, Zaragoza, Spain.
⁴ Department of Anatomy, Embryology and Genetics, CIBERCV, Faculty of Veterinary Medicine, University of Zaragoza, Zaragoza, Spain.

Abstract

The aim of this research was to compare the different techniques to measure sperm nuclear DNA fragmentation (sDF) and to check its relations to boar reproductive value, classical spermiogram parameters, and reproductive results of the doses in sows. Sperm chromatin stability assay (SCSA), terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and sperm chromatin dispersion test (SCD, Halomax^®) results were compared, finding a statistically significant correlation only between SCSA and TUNEL results. The fertility direct boar effect (DBE) index, calculated from the whole productive life of the boar, was not correlated (p > 0.05) with sDF (measured by any technique). Total or progressive sperm motility was not correlated with sDF, while it found a positive correlation between TUNEL measure and abnormal acrosomes (%) and between SCD measure and total sperm morphological abnormalities (%). No significant correlations were obtained between fertility or prolificacy results and sDF results with the different techniques. However, in the case of total born and SCSA measure, the correlation was close to significance (r partial = -0.095; p = 0.066), appointing to a tendency; as SCSA increases, the number of total piglets born decreases. In conclusion, although the different techniques for the sDF seem not to target exactly the same DNA events and the relationship between their values and the reproductive results and the classical spermiogram results is still to be elucidated, the studied sDF techniques may offer extra information that could be useful for the management of AI studs.

Keywords: SCD; SCSA; TUNEL; boar; fertility; fragmentation; sperm DNA fragmentation (sDF).