| dc.description.abstract | The technique of pre-IVM subculture has been studied to help small oocytes collected from 2-3
mm follicles have the same maturation rate and development ability as large oocytes from 4-6 mm
follicles. In this study, we do three experiments. First, study the maturation rate of small oocytes
when cultured in pre-IVM and in the non pre-IVM medium. Next, we examined the rate of male
nucleus formation from dead sperm of small oocytes cultured by the pre-IVM technique. And
finally, the inter-species embryo development was evaluated when dead gaurus sperm was injected
into golden cow's small oocytes by intracytoplasmic sperm injection (ICSI) technique. As a result,
pre-IVM improved the small oocytes maturation rate from 41.7% to 79.7%. In addition, the sperm
head was still retained in the oocytes when not cultured in pre-IVM, while 57% and 66% of the
zygotes cultured in the pre-IVM medium had male pronucleus formation. When examining hybrid
embryos from small antral follicles cultured in a pre-IVM medium, only 36.4% of embryos
reached 4-cells and none reached 8-cells or morula. In summary, pre-IVM culture improved the
maturation rate and formation of male pronuclei from dead sperm in small antral follicles, embryos
in this group can reach to 2-4 cells. However, still can not develop to look like fully grown oocytes. | en_US |
