Investigations of BrdU incorporation in roe deer blastocysts in vitro

These data provide direct evidence for slow proliferation activity in pre-implantation roe deer trophoblasts and even minor growth of the embryoblast. The blastocyst grows very slowly from August to January. Incorporation of BrdU into the nuclei during a period of 4 h was used to determine the proliferation of the embryonic cells in vitro. The results show for the first time the DNA synthesis in trophoblast cells of roe deer blastocysts from October to December. During the period of October to November the incorporation of BrdU is weak, and in December there is a duplication of DNA metabolism.