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. From 372 reconstructed embryos, 188 (50.5%) reached the morula stage and 117 (31.5%) developed to blastocysts after vitrification. Transfer of 98 (26.3%) morphologically normal blastocysts gave rise to 6 (1.6%) piglets, including 1 stillborn. The efficiency of the cloned piglet production was comparable with that obtained using SCNT embryos without cryopreservation (2.7%, 17/635). Here, we demonstrate that porcine somatic cell cloning can be performed without a significant reduction in efficiency even when the SCNT embryos are cryopreserved before transfer.
Department of Life Sciences, School of Agriculture, Meiji University, Kanagawa, Japan.
Kazuaki
K
Nakano
Hitomi
H
Matsunari
Naoki
N
Nakayama
Buko
B
Ogawa
Mayuko
M
Kurome
Masashi
M
Takahashi
Mitsuhito
M
Matsumoto
Hitoshi
H
Murakami
Yuji
Y
Kaji
Hiroshi
H
Nagashima
D000818:Animals; D019976:Cloning, Organism; D015925:Cryopreservation; D008055:Lipids / Q000302:isolation & purification; D009028:Morula; D053652:Nuclear Transfer Techniques; D013552:Swine; D058989:Vitrification
D008055:Lipids