Normally, the presence of the corpus luteum, which is formed after ovulation, is important for animals, including humans, to maintain pregnancy.In rodents such as mice, the corpus luteum regresses rapidly after formation, but copulation stimulation with males prolongs the existence period and maintains pregnancy. there were.

　In 2020, the research group independently developed a device that reproduces male mating stimulation using sonic vibrations, and artificially created a pregnancy environment for female rats.This time, by improving the device, they succeeded in artificially creating a pregnancy environment even in mice.

　In addition, as a result of transplanting genome-edited frozen fertilized eggs using the take method (electroporation) into females in which the gestation environment was artificially created, we succeeded in producing genetically modified offspring.Normally, the gestational environment for females is established from the day before transplanting the fertilized eggs, but by this method, the gestational environment could be established instantaneously on the day of transplantation.

　This technology, called fertilized egg transfer, is an important technique used in the production of genome-edited animals and the planned production of industrial animals, and is expected to be widely used in the future.In addition, since this research has succeeded in mice and rats, which are often used in basic medical research, it is expected to be applied to elucidation of pregnancy mechanisms in animals including humans, research into infertility, and artificial breeding of endangered species.The developed equipment has been commercialized and preparations for sales are underway.It is possible to use animals systematically, and as a result, it is possible to reduce the number of animals used, which contributes to animal welfare.

Paper information:[Scientific Reports] Successful induction of pseudopregnancy using sonic vibration in mice