34. Animals providing DNA for nuclear transfer will usually have been humanely killed. Indeed the cell culture which gave rise to Dolly was apparently taken from a sheep slaughtered some time previously. Those animals providing cells to receive the DNA will have been superovulated prior to humane killing and removal of oocytes post mortem. Following nuclear transfer, oocytes are cultured in vivo in the ligated oviduct of a live sheep for a period of about one week. These animals are able to carry large numbers of oocytes but are humanely killed when the developed blastocysts are transferred to recipients. The accrued stress to these animals of a surgical procedure with recovery, followed by killing, is not insignificant. It should be possible to develop an in vitro culture method to avoid the use and killing of such animals.
35. Surgical intervention of animals used for in
vivo culture with subsequent killing should be
avoided. Further research is required to minimise stress in, and
avoid wastage of, such animals. Research should also be
undertaken to develop in vitro