Defining the requirements for bovine embryo culture

There are several culture systems which support the development of bovine embryos in vitro. By far the most popular method is co-culture with somatic cells, but increasingly defined mono-culture systems are also a practical alternative. To develop a defined system requires knowledge of: the biochemical requirements for embryo development; the composition of the in vivo environment. Neither of these are constant during embryo development, yet most laboratories continue to grow embryos under relatively static conditions. A new approach is to perfuse embryos with a medium in which gradient changes in both physical and chemical conditions can be introduced over time. Perfusion culture of embryos offers a number of advantages over static conditions and it is proposed that such systems will become increasingly popular in the future.