Definition of fusion medium and electric parameters for efficient zygote electrofusion in the Pacific oyster (Crassostrea gigas)

When pulses were applied for first time, it was determined that an ionic fusion medium (microfiltered seawater) offered better conditions than the non-ionic fusion media previously used (0.6 M sucrose or 0.6 M mannitol) in terms of embryo survival and lysis rates. In this fusion medium, two different combinations of electric parameters (3 square DC pulses of 400 Vcm−1 for 50 μs each at 26 °C and 1 square DC pulse of 600 Vcm−1 for 50 μs at 26 °C) offered the best technical results of fusion (57 and 79% respectively) and survival until D-larva (44 and 41% respectively). In conclusion, these electric parameters could be established, using seawater as electrofusion medium, for further approaches to evaluate individual ploidy and survival beyond spat.