title: Comparative morphologic placental types in Dasypodidae (Chaetophractus villosus, Cabassous chacoensis, Tolypeutes matacus and Dasypus hybridus).
abstract: Information about the morphology of placentas in armadillos is scarce, except for D. novemcinctus. A comparative study of morphologic placental types in armadillos is important in order to have a comprehensive view of the peculiar reproductive physiology in this family. The aim of this paper is to perform a comparative analysis of the morphological features of the placenta in Chaetophractus villosus, Cabassous chacoensis, Tolypeutes matacus and Dasypus hybridus in order to classify them in accordance with Grosser (1909). The placentas were studied macroscopically and histologically (light microscopy in 1 micron thick sections and electron microscopy for fine structure). The macroscopic study in the 4 studied species showed a similar pear-shaped placenta homogeneously villosus in almost all the surface. The histological analysis showed that the 4 studied species had a hemochorial type of placenta. This type of placenta was also found in D. novemcinctus (Dasypodidae), but it is different from those described for other xenarthrans. Hemochorial types of placenta have also been described in more modern mammals. Despite the many primitive features of the armadillos and the different anatomical and physiological features between the genuses of dasypodids, all the studied species share this structural type of placenta.
authors.affiliation: Center of Research in Reproduction, School of Medicine, University of Buenos Aires, Paraguay 2155, 1121 Buenos Aires, Argentina.
authors.forename: V C
authors.initials: VC
authors.lastname: Adamoli
authors.forename: P D
authors.initials: PD
authors.lastname: Cetica
authors.forename: M S
authors.initials: MS
authors.lastname: Merani
authors.forename: A J
authors.initials: AJ
authors.lastname: Solari
mesh_terms: D000818:Animals; D001135:Armadillos / Q000145:classification / Q000196:embryology*; D005260:Female; D010920:Placenta / Q000033:anatomy & histology* / Q000648:ultrastructure; D011247:Pregnancy