A complete culture system for the chick embryo.

The embryonic lifespan of the chick is 22 days. Development in the first day takes place in the oviduct, and in the remaining 21 days in the shelled egg. There have been few attempts to culture oviductal embryos, though methods covering the first few days of development in ovo are well established and a method for the final 18 days of development through hatching has recently been devised. I have now succeeded in culturing the fertilized ovum of the chick (Gallus domesticus) for the total embryonic period by growing it in a series of separate culture systems. This is the first report of a complete in vitro method for a homoiothermic animal. The technique opens the way to the investigation of developmental events in birds that require access to the embryo at the single-cell stage, and in particular to the genetic manipulation of the fertilized ovum.