Abstract
Ph.D. (Zoology)
This project involves a detailed study of three South African antelope species,
springbok, impala and blesbok. The study investigates the origins of sperm in terms of
testicular histology and subsequently the major storage organ, the cauda epididymis.
Sperm of these species were characterized in terms of their quality (morphology,
motility, vitality characteristics among others and their physiology: when exposed to
different media and cryopreservation protocols. Finally sperm fertilization biology of the
three species and evaluation of fertilization and developmental success when using
homologous and heterologous oocytes (relative comparison) were assessed.
Cauda epididymal spermatozoa was recovered post-mortem from the testes of culled
springbok (n =38); impala (n =26) and blesbok (n =42) during winter months in South
Africa and cryopreserved in a Tris-fructose-citric acid extender (Biladyl) supplemented
with 20% egg yolk and 7% glycerol under field conditions. Longevity of sperm was
assessed in Tris and Citrate extenders and modified Tyrode lactate in vitro fertilization
(IVF) media. Oocytes were collected from the ovaries of domestic cows (n =165),
springbok (n = 72) and blesbok (n = 42) and matured in domestic cattle M199
maturation media supplemented with 10% FCS, 10IJg/mi LH, 10IJg/mi FSH and
antibiotics. Heterologous (zona intact and zona free) and homologous fertilization was
carried using a domestic cattle IVF protocol.
Results were analysed using SPSS version 18.0 (Statcon, South Africa). Interspecies
comparisons were made using parametric tests: paired t-test for the freezing effect,
one-way analysis of variance (ANOVA), Mixed between-within subjects ANOVA for
longevity, Non Parametric test for motility characteristics and least squares ANOVA for...