Transplantation of Preimplantation Hamster Embryos

Since Heape (1890) first succeeded in transplanting rabbit embryos (four-cell stage), the transplantation of fertilized eggs and preimplantation embryos of laboratory animals has been progressively more successful (for review and bibliography, see Chang & Pickworth, 1969; Adams & Abbott, 1971), though few studies seem to have been made on the transplantation of hamster embryos. Blaha (1964) reported that 49·2% of six- to eight-cell embryos from young (2½- to 6-month-old) donor hamsters could develop into term fetuses when transplanted into young recipients, but that only 8·3% of embryos of the same developmental stage developed into fetuses when transplanted into old (14- to 10-month-old) recipients. The incidence of successful fetal development was also very low (4·5%) when the embryos from old donors were transplanted into young recipients. Orsini