Oviductal

Next Reports Eight Calves Cloned from Somatic Cells of a Single Adult Yoko Kato, Tetsuya Tani, Yusuke Sotomaru, Kazuo Kurokawa, Jun-ya Kato, Hiroshi Doguchi, Hiroshi Yasue, Yukio Tsunoda * Eight calves were derived from differentiated cells of a single adult cow, five from cumulus cells and three from oviductal cells out of 10 embryos transferred to surrogate cows (80 percent success).

Eggs were collected 13 to 15 hours after the hCG injection from the oviductal ampulla region under paraffin and were placed in a 400 µl drop of TYH medium (24) equilibrated with 5% CO 2 in air at 37°C. Zona-free eggs were prepared by acidic tyrode according to the method described [B. Hogan, F. Costantini, E. Lacy, Manipulating the Mouse Embryo (Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 1986)].

[View Larger Version of this Image (106K GIF file)] A fourth surrogate in series C maintained pregnancy after the oviductal transfer of 36 cloned embryos that were derived from fibroblast cultures at passage two.