Production of bovine tetrapolid embryos by electrofusion and their developmental capability in vitro

Abstract
Optimal conditions of electrofusion for blastomeres of two‐cell bovine embryos to produce tetraploid embryos were investigated. The high fusion rate (73–95%), viability, and develop mental capacity were obtained under a field strength of 1.0 kV/cm with direct current pulses of 10 or 25 μsec duration applied twice. Cytological study showed that 78.6% (11/14 embryos) of embryos exposed to electrofusion had tetraploid chromosome sets and the others were diploid or hexaploid. The tetraploid embryos had the capability to develop up to morulae stage in vitro.