In vitro development and postvitrification survival of cloned feline embryos derived from preadipocytes.

The aim of the present study was to optimize the conditions for in vitro development and postvitrification survival of somatic cell cloned feline embryos. To determine the effects of cell cycle synchronization of the nuclear donor cells, we cultured preadipocytes under serum starvation or conventional conditions. After two days in serum starvation culture, the proportion of synchronized donor cells at the G0/G1 phase was 91.

Cloned porcine embryos can maintain developmental ability after cryopreservation at the morula stage.

The aim of the present study was to clarify the overall efficiency of porcine somatic cell nuclear transfer (SCNT) by incorporating cryopreservation of the cloned embryos before transfer. The SCNT embryos reconstructed with preadipocytes and in vitro-matured (IVM) oocytes were cultured to harvest morula stage embryos; they were then subjected to delipation (removal of cytoplasmic lipid droplets) and vitrification. After warming and culture, the embryos developing to blastocysts were transferred to recipients to obtain cloned piglets.

Developmental ability of porcine in vitro matured oocytes at the meiosis II stage after vitrification.

The aim of the present study was to investigate whether a combination of cytoplasmic lipid removal (delipation) and treatment by a microtubule stabilizer, paclitaxel, would lead to efficient cryopreservation of porcine in vitro matured (IVM) oocytes at the meiosis II (MII) stage. Vitrification and subsequent re-warming and culture of 109 untreated oocytes produced only 9 blastocysts (8.3%).