The in vitro culture of primitive-streak-stage mouse embryos

The in vitro growth and morphogenesis of mouse embryos from early primitive-streak stage to early-somite stage is described. The embryo culture method employs a static culture system, a conventional chemically defined medium (Dulbecco's modified Eagle's medium), supplemented with additional glucose, glutamine and suitably prepared serum. The method of serum preparation is important for successful culture. Both mouse serum and rat serum support good development of primitive-streak-stage mouse embryos. Over 60% of early-streak stage and about 90% of late-streak stage grow and develop for 48 h in vitro. During the first 24 h in culture, total growth of the embryos as reflected by protein content, size and morphology is the same as in vivo.