In vitro embryo culture technique

A process for the in vitro culture of an avian embryo up to blastoderm formation, during embryonic morphogenesis and during embryonic growth to hatch, the process comprising culturing an avian embryo by a process comprising culturing a fertilized avian ovum, having a surrounding capsule of dense albumen, partially subemreged in culture medium in a first container sealed with a film having low gas permeability and not naturally associated with an resultant avian egg, up to blastoderm formation, subsequently culturing the avian embryo by a process comprising incubating said avian embryo during embryonic mrophogenesis in a culture medium in a liquid-filled liquid-impermeable second container sealed with a partially gas permeable film, and subsequently culturing the resultant avian embryo by a process comprising incubating said avian embryo during the embryonic growth phase in a closed second or third container, there being an air space above the embryo, the air space being separated from the external atmosphere by a partially gas permeable film, said incubating continuing until said embryo hatches.