view - Department of Reproduction, Obstetrics and Herd Health

CHAPTER 5
This thesis originated from the practical challenges faced when optimizing cryopreservation
of equine semen at our clinic. Our original cryopreservation protocol was based on old-fashioned
handiwork using the same protocol for all stallions. Gradually, the cryopreservation protocol evolved
and reached new levels, until one realized what it actually is: “the art of freezing”. As with any form
of art, or science, the correct nomenclature plays a key role in discussing the topic, and a Babel-like
confusion of tongues was and is present amongst scientists dealing with animal semen quality and
cryopreservation. Unlike human andrology, anarchy rules in this veterinarian kingdom. Hence this
anarchy needs to be replaced by a code in which scientists have agreed upon : (1) criteria and
settings used for sperm analysis in order to gain consensus between different laboratories ; (2)
standards for sperm manipulation procedures, and (3) definitions for semen quality parameters in
different domestic species. In this thesis, we have taken the first two steps towards the generation of
such a code by describing how settings for sperm quality assessment and how manipulation of
semen can affect the eventual outcome of a sperm quality assessment in the horse. I hope that more
studies of this kind, in the horse but also in other species, can lead to the generation of a code or a
manual describing guidelines and strict criteria for sperm quality assessment in domestic animals, as
it has already been done for human in the WHO Manual. In the next paragraphs, the importance of
using the right nomenclature, applying standardized equipment and manipulating semen using strict
criteria, is discussed.
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