Birth of Cloned Calves Derived from Cultured Oviductal Epithelial Cells of a Dairy Cow

The present study aims to examine the effects of the use of two kinds of somatic cells from a single adult cow on fusion rate, cleavage rate, developmental rate into blastocysts of nuclear transplant oocytes, and pregnancy potential of reconstituted blastocysts. Oviductal epithelial cells and mammary gland cells from a single adult Jersey cow with a milking record were used in the present experiment. No significant differences were observed in the in vitro criteria described above between two cell types used as a source of donor nucleus. Although pregnancies were obtained from both cell types, live calves resulted only from embryos cloned from oviductal epithelial cells. Using oviductal epithelial cells, three out of ten recipients became pregnant. Two carried to full term and delivered one female calf each at day 285 of gestation. The birth weights of two live female calves were 27.5kg and 30.0kg. The third aborted at day 251 of gestation. On the other hand, using mammary gland cells, one out of six recipients became pregnant but aborted at day 81 of gestation. Genomic DNA analyses confirmed that the calves are all genetically identical to the nuclear donor cell.