Sperm chromatin structure and sperm morphology: Their association with fertility in AI-dairy Ayrshire sires

S. Nagy, A. Johannisson, T. Wahlsten, R. Ijäs, M. Andersson, H. Rodriguez-Martinez

Research output: Contribution to journalArticle

21 Citations (Scopus)


Prognostic relations between sperm variables and sire fertility are yet elusive. A retrospective analysis of sperm morphology and chromatin stability (studied using sperm chromatin structure assay [SCSA]) and their relation to fertility after AI (as proportions of 60 days of nonreturn to estrous [NRR], corrected NRR, or calving rate) was studied with preselected frozen semen doses from a group (N = 43) of AI-sires of the Finnish Ayrshire breed composed of 50% subfertile bulls (<55% NRR) and 50% fertile sires (>55% NRR). Fertility, indicated by all three parameters, correlated significantly only with the percentage of morphologically normal spermatozoa, a variable which negatively correlated with the percentage of DNA fragmentation at the time of SCSA, thus confirming the value of always having high numbers of morphologically normal spermatozoa in AI-doses. Proportions of major sperm defects also related to fertility but only when considering corrected NRR, not with calving rate, indicating that proportions of normal spermatozoa, a value surpassing differences between sperm laboratory screening methods, might be valuable and could be easily made routine by the industry. Though SCSA as a method is being contested for DNA- and chromatin analyses in the light of epigenetic changes, a particular parameter, the High Green fluorescence, showed the highest values for sperm doses collected from bulls having meiotic problems and containing a high proportion of diploid spermatozoa (approximately 20%) and also in bulls having a reciprocal chromosomal translocation, thus suggesting such a parameter might be useable to discriminate which bulls ought to be studied in more detail, including cytogenetic analyses.

Original languageEnglish
Pages (from-to)1153-1161
Number of pages9
Issue number8
Publication statusPublished - May 1 2013



  • Bull
  • Fertility
  • Sperm chromatin integrity
  • Sperm morphology

ASJC Scopus subject areas

  • Small Animals
  • Food Animals
  • Animal Science and Zoology
  • Equine

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