| dc.description.abstract | Somatic cell nuclear transfer (SCNT) is a technique used to create cloning embryos
and has a variety of applications. However, the availability of oocytes at fully
grown stage is scarce. Oocytes obtained from ovaries are mainly at antral stage.
While large antral follicles-derived oocytes can become mature and show great
ability to generate embryos after SCNT by in vitro maturation (IVM) culture, their
smaller counterparts face more challenges. Therefore, a pre-IVM culturing process
prior to IVM was suggested. Nevertheless, the pre-IVM protocol that proves to be
effective in supporting oocytes and can displace high developmental competence
post-SCNT are not yet to be established. Thus, this study was conducted to
complete such task. As the results indicated, pre-IVM culture did enhance meiosis
rate in small-sized oocyte which was comparable to fully grown ones at
approximately 80%. Improvements also showed in the developmental
competence of parthenogenetic embryos reconstructed from small oocytes. The
proportion of good-quality blastocyst based on the blastomere number was
recorded even higher in group of pre-IVM and L-ascorbic acid treatment than
positive control group (55.70% versus 53.90, respectively). Alike outcome was
observed in the histone H3K9 acetylation intensity measured in parthenogenetic
blastocysts after immunostaining. Such results indicated establishment of a pre IVM protocol that may support small antral follicles-derived oocytes for SCNT.
Regarding to the developmental ability of SCNT embryos derived from small-sized
oocytes after pre-IVM culture, the percentages were comparable to the positive
control group despite large deviation. Nonetheless, such pre-IVM protocol was able
to generate embryo reached late blastocyst stage. Taken together, the pre-IVM
medium used in this study might have the potential to improve developmental
competence of small oocytes undergoing SCNT and yet, more tests need to be
carried out. | en_US |
