SEPARATION TECHNIQUES TO ACHIEVE SUBPOPULATIONS OF VITAL AND FERTILE EQUINE SPERMATOZOA - A SURVEY

Equine ejaculates are significantly characterized by widely varying pa rameter; especially in those of practical relevance for equine Al. The refore it is of interest for practical purposes to get subpopulations of concentrated, vital, and competent spermatozoa from the origin ejac ulates. Special preparation of the donor stallions will stabilize sper m output. Fractionated semen collection from stallions supplies sperm enriched seminal fractions very useful to work with further in semen p reservation. Most important to achieve a concentrated sperm subpopulat ion are semen manipulations post ejaculation represented conventionall y in semen centrifugation. In the fast decade alternative measurements have been introduced. Above ail semen filtration using glasswool-seph adex and more recently membrane techniques gave good results indicatin g that these new techniques may replace semen centrifugation in the fu ture. This article gives a survey of the different starting points and methods far separation of Vital and concentrated sperm subpopulations of equine semen.