Interspecific chimaerism between sheep and goat

In rodents, chimaeric blastocysts produced by combining embryonic cells of two different species have been used in investigations of cell lineage and interaction during development (Mus musculus-Rattus norvegicus^1,2, M. musculus-Clethrionomys glareolus³, M. musculus-Mus caroli⁴). However, interspecific chimaerism also offers new approaches to the study of reproductive incompatibilities between species and may even allow such incompatibilities to be neutralized, thus improving the chances of successful hybridization and interspecific embryo transplantation⁵. We report here the production of sheep-goat chimaeras by embryo manipulation and the use of interspecific chimaerism to allow successful interspecific embryo transplantation in sheep and goats.