Embryo transfer in sheep under practice conditions.

Embryo transfer was carried out on nine Texel donor ewes, one of them on two occasions, over two breeding seasons (1980 and 1981). The donors were prepared for superovulation on the farm by two different regimens and the recipients were also synchronised on the farm of origin. Surgery was carried out on donors and recipients at a veterinary practice and the techniques of anaesthesia, surgery and embryo transfer are described. Superovulation was variable and more than two ovulations were seen in only four of the 10 ewes. Forty-one corpora lutea were produced by the 10 ewes and 27 embryos were recovered. Twenty-one embryos were transferred to recipients and 14 lambs were produced. All the 10 donors except one produced lambs themselves. The value, economics and welfare aspects of the technique of embryo transfer under practice conditions are discussed and it is concluded that the procedure should not be carried out routinely but reserved for special circumstances.