Submitted December 19, 2003
Returned for revision January 13, 2004
Accepted May 12, 2004
Reproductive Technology
Post-Thaw Evaluation of In Vitro
Function of Epididymal Spermatozoa from Four Species of
Free-Ranging African Bovids
Jason R. Herrick ,
Paul Bartels ,
and
Rebecca L. Krisher *
* To whom correspondence should be addressed. E-mail: rkrisher{at}purdue.edu.
Abstract
An improved understanding of reproductive physiology in
nondomestic bovids is necessary for the development of
assisted reproductive technologies (ART) for use in the
conservation of endangered bovids. In this study
epididymal spermatozoa were recovered from blesbok
(Damaliscus dorcas phillipsi), African buffalo
(Syncerus
caffer), springbok (Antidorcas marsupialis),
and black
wildebeest (Connochaetes gnou) following organized
culls
in South Africa. Our objectives were to: 1) characterize
the quality of epididymal spermatozoa; 2) evaluate the
effectiveness of a cryopreservation protocol; 3) compare
post-thaw sperm longevity (motility, viability, and
acrosomal integrity) and functionality in two culture
media with two capacitation reagents (caffeine and
heparin). Following recovery, spermatozoa were diluted in
EQ extender, slow cooled, and frozen in the presence of 5%
glycerol. Thawed spermatozoa were separated on a Percoll
gradient and diluted in SOF for fertilization (SOFfert;
0.6% BSA, 0.0 mM glucose, 25.0 mM NaHCO3) or modified
SOFfert (modSOFfert; 1.2% BSA, 1.5 mM glucose, 37.0 mM
NaHCO3) and either heparin or caffeine and incubated for
6h. Spermatozoa from these species maintained an average
of 64% of initial motility after thawing. Incubation
medium and capacitation reagent had species-specific
effects on the motility, viability, and acrosomal
integrity of spermatozoa, suggesting ART procedures need
to be optimized for each species. Springbok spermatozoa
were also shown to be competent for in vitro
fertilization. Information from this study concerning
sperm physiology in blesbok, African buffalo, springbok,
and black wildebeest will be useful in the development of
ART for the conservation of these and other species of bovids.
Key words:
Gamete Biology •
Assisted Reproductive Technology •
In vitro fertilization •
Sperm •
Sperm capacitation
