Postimplantation development of CB-induced triploid mouse embryos.

By subjecting A strain eggs at the time of fertilization and polar body extrusion to 5 micrograms/ml cytochalasin B, digynic triploidy was produced in 80% fertilized eggs. Triplonucleate eggs were transplanted to recipients and examined between 9-11th day of pregnancy. Development of triploid mouse embryos up to day 7 is normal and most embryos form early egg cylinder. At day 8 the embryonic part of the cylinders is under-developed and later development fails to form an embryo. Development of foetal membranes is much less affected, CB-induced triploids survive to 10th- day of pregnancy.