Abstract: Methods for the activation of nuclear transferred embryos using elevated calcium levels introduced into cells, and a maturation promoting factor (MPF) inhibitor are described. Elevated calcium levels introduced into the embryo cells from a culture medium containing elevated calcium levels, in the range 2 mM to about 12 mM, followed directly and immediately by incubation with DMAP are described. Also described are animals produced from embryos so treated.

Abstract: Methods for the production of nuclear transfer embryos, nuclear transfer embryos and animals derived therefrom are described. The method generally comprises at least the steps of: providing at least one enucleated recipient cell; providing at least one donor cell or nucleus; providing a fusion media which is substantially free of calcium; placing said at least one enculeated recipient cell and at least one donor cell or nucleus in contact with one another to form couplets; and, fusing via electrofusion in said fusion media said at least one recipient cell with at least one donor cell or nucleus to form a nuclear transfer embryo.