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CHAPTER 4
Parthenogenetic development of porcine oocytes
synchronised by CHX or cAMP and maturation
timing of cAMP treated oocytes for TI enucleation
4.1 INTRODUCTION
The term parthenogenesis was first employed by Richard Owen referring to
reproduction without the immediate influence of a male (Owen, R., 1849).
Subsequently parthenogenesis was redefined as "the production of an embryo, with or
without eventual development into an adult, from a female gamete in the absence of
any contribution from a male gamete" (Kaufman, 1979).
Oocytes can be parthenogenetically activated physically and chemically. There are a
lot of factors influencing the results of parthenogenetic activation, including oocyte
age, activation media, duration and strength of electric stimulation and post-treatments
(cytochalasin B or D, CHX and 6-DMAP, etc. ). Oocytes activated by different
methods may not have equal competence for development. In addition, various results
have been evaluated to determine the success of parthenogenetic activation such as
the frequency of pronucleus formation, cleavage or blastocyst and the total cell
number at blastocyst stage.
Porcine parthenotes have been obtained using a range of activation stimuli including
ethanol (Didion et al., 1990), electroporation (Hagen et al., 1991), calcium ionophores
(A23187; Funahashi et al., 1994), electroporation plus CHX (Nussbaum and Prather,
1995), ethanol plus CHX (Petr et al., 1996), staurosporine (Wang et al., 1997b),
thimerosal (Machäty et al., 1997), electroporation plus butyrolactone I (Dinnyes et al.,
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