Development of an Artificial Fertilization Method for the Japanese Pearl Oyster Pinctada fucata martensii by Using a Microplate

摘要

Japanese pearl oysters are widely cultivated by artificial fertilization using gametes obtained from the ovary and testis. Using the gametes from the Japanese pearl oyster, we developed a method for conducting small-scale artificial fertilization tests in a 24-well microplate. Following induction of germinal vesicle breakdown (GVBD), we inseminated 20,000 eggs in 2.0 ml seawater in a single well of a microplate. The highest fertilization rates were obtained using a testicular semen volume of1.25 julwhen the concentration of NH3 in seawater was 0.75 mM during insemination. Changes in contact time (the time from commencement of insemination to rinsing the eggs) from 3 to 60 min did not affect the fertilization rate. However, a contact time of >12 minwas necessary to ensure consistency in contact time among the 24 wells.