Placental structures and their association with matrotrophy and superfetation in poeciliid fishes

We describe the ultrastructure of the maternal follicular placenta of 11 poeciliid fishes using electron microscopy. In addition, we quantified six ultrastructure characteristics that reflect the degree of complexity (number of vesicles, area of vesicles, number of microvilli, microvilli length, thickness of the maternal follicle and follicular area). Using phylogenetic comparative methods, we evaluated the relationship between degree of matrotrophy and placental characteristics. We also analysed the potential effect of the presence of superfetation on placental complexity. We found a positive relationship between the degree of matrotrophy and follicular area, number of microvilli and number and area of vesicles. Similarly, follicular area and number of microvilli were larger in species with superfetation than in those without superfetation. We conclude that high degrees of matrotrophy and superfetation are associated with placental characteristics that increase the efficiency of nutrient transfer between mother and embryos.

Source: Acta Zoologica - February 2, 2018 Category: Zoology Authors: Claudia Olivera ‐Tlahuel, Norma A. Moreno‐Mendoza, Maricela Villagrán‐Santa Cruz, J. Jaime Zúñiga‐Vega Tags: ORIGINAL ARTICLE Source Type: research