Parthenogenetic activation of mouse and rabbit eggs by electric stimulation in vitro

The present study was undertaken to determine conditions for parthenogenetic activation of mouse and rabbit eggs by electric stimulation in vitro. The cumulus-free eggs were submitted to square direct current pulses at output voltage of 1.0 to 2.5 kV/cm for 25 to 200 microseconds. The best conditions for the activation of mouse eggs were 1.5 kV/cm for 100 microseconds, in which 78% of eggs were activated, 32% of which developed to blastocysts in vitro. When the nonelectric solution (0.3M mannitol) was used for electric stimulation, the activation rate was quite low (16%). Optimal conditions for activation of rabbit eggs were 1.5 kV/cm for 200 microseconds, in which 77% of eggs were activated, 25% of which developed to blastocysts. Unlike mouse eggs, rabbit eggs frequently had three pronuclei after electric stimulation. It is clearly shown that electric stimulus can induce parthenogenetic activation of the mouse and rabbit eggs in vitro.