IXth International Conference on Boar Semen Preservation 2019

The fate of spermatozoa in the female reproductive tract: A comparative review (61191)

Jessica Rickard 1 , KR Pool 1 , X Durant 2 , S de Graaf 1
  1. Faculty of Science, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
  2. Station de Physiologie de la Reproduction, Institut National de la Recherche Agronomique, Nouzilly, 37380, France

The journey that spermatozoa take following deposition in the female tract is a long and perilous one.  The barriers which spermatozoa are faced with in the female tract differs depending on whether spermatozoa are deposited in the vagina or uterus, like that of the ram or boar respectively.  Comparing the transit of spermatozoa through the ewe and sow serves to highlight similarities or differences in terms of how their sperm-surface properties enable spermatozoa to overcome these barriers, progress through the tract and fertilise the oocyte.  The female environment contributes towards this successful transit by providing a vehicle for sperm transport, aiding the removal of dead spermatozoa and other pathogens and applying strict selection pressures to ensure only those spermatozoa with the highest quality reach the site of fertilisation.  Understanding the criteria behind these natural pressures helps to assess the limited fertility associated with preserved spermatozoa and how in vitro manipulation can alter this complex interaction between spermatozoa and the female environment, with the end goal of improving the success of assisted reproductive technologies for animal production industries.  Similar mechanisms or surface coat interactions exist in both species, but each have evolved to be used for physiologically disparate functions.  Here we briefly describe the sperm surface characteristics of both fresh and frozen-thawed boar and ram spermatozoa and compare how these properties equip spermatozoa to survive the physical, biochemical and immune interactions within the female reproductive tract.