Development of a culture medium (BECM-3) for porcine embryos: effects of bovine serum albumin and fetal bovine serum on embryo development.

Media are available that can deliver modest porcine embryonic development from a single-cell zygote to the blastocyst stage. However, few embryos develop to hatched blastocysts by Day 7 in vitro, indicating deficiencies in media that inhibit early embryonic development. A defined culture medium, Beltsville Embryo Culture Medium (BECM-3), was developed to support porcine zygote development to the blastocyst stage. When fetal bovine serum was added by late Day 5 (late morula/early blastocyst stage), 80% of total embryos cultured from Day 2 developed into hatched blastocysts by Day 8. There was also a significant increase in the mean cell number of blastocysts and hatched blastocysts when culture was performed in BECM-3-based media in the absence of BSA fraction V. These studies provide a chemically defined foundation for elucidating key developmental components of preimplantation pig embryos.