Development of embryos cloned from cells of three different Yasufuku cell lines.

*Fusion was examined one hour after electrofusion of couplets of cells and enucleated oocytes. Percentage of the number of the couplets.?Blastocyst development was examined 168 h after nuclear transfer. Percentage of the number of cultured embryos.?Single blastocysts were transferred into single synchronized recipients. Several blastocysts were stored in liquid nitrogen by a vitrification technique. Ten vitrified and warmed embryos were transferred to recipients.?Pregnancy was examined by ultrasonography at 33 days after embryo transfer. Percentage of the number of transferred recipients.aOne recipient delivered a healthy male calf on 30 November 2007. One delivered a mummified fetus on 27 August 2007. One recipient that received a vitrified embryo delivered a healthy male calf on 5 March 2008 but the calf died two days after birth.bTwo recipients, which received vitrified embryos delivered two healthy male calves on 22 and 31 July 2008.