Embryo Transfer Technologies in Pigs

Abstract

Embryo transfer (ET) became a reality in the swine industry with the birth of the first live ET piglets in 1950. Since that pioneering achievement more than 68 years ago, significant developments in porcine ET and its related technologies have occurred. Although the volume of commercial ET activity with pigs is low compared to that reported for cattle, substantial porcine ET activity is taking place in private companies and institutes engaged in biomedical research. In vitro production of pig embryos has greatly surpassed that of in vivo-derived embryos, and development of nonsurgical methods for transfer of swine embryos has opened the door to potential widespread commercial application of porcine ET. The historical inability to cryopreserve pig embryos has been overcome to a great extent with development of protocols for vitrification of porcine embryos. The creation of genetically modified pigs via somatic cell nuclear transfer or genome-editing technologies depends upon successful ET, and the needs of the biomedical research community likely will be the impetus for further refinements in pig ET technologies.