Placental Evolution within the Supraordinal Clades of Eutheria with the Perspective of Alternative Animal Models for Human Placentation

Figure 4

Placentation in Laurasiatheria. (a) Chorioallantoic placenta in a carnivore, the coati Nasua nasua, with nests of cytotrophoblast in the barrier and a maternal vessel with intact endothelium, representing an endotheliochorial type of placentation. Derived from [260]. (b) The synepitheliochorial bovine placenta near term with binucleate giant cells and fetal capillaries between the trophoblast cells. Derived from [104], modified. bgc = binucleate giant cell, ct = cellular trophoblast, endo = endothelium, fc = fetal capillary, mv = maternal vessel, trp = trophoblast, and ue = uterine epithelium.

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