Laboratorio de Histología y Embriología Descriptiva, Experimental y Comparada, Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata, La Plata, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina.
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina; Laboratorio de Análisis de Imágenes, Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata, La Plata, Argentina.
Zoology (Jena). 2023 Jun;158:126082. doi: 10.1016/j.zool.2023.126082. Epub 2023 Mar 7.
Reproductive specializations in caviomorphs (infraorder Hystricognathi), are very peculiar within the Order Rodentia. These include long gestations, the birth of offspring with an extreme degree of precociality, and short lactation periods. This study describes the embryo-placental relationship of viable implantation sites (IS) of the plains viscacha, Lagostomus maximus, after 46 post-coital days. The observations recorded in this study are comparatively discussed with those of other hystricognaths and eutherians. At this stage, the embryo resembles that of other eutherians. At this time of embryo development, the placenta exhibits a size, shape, and organization similar to that it will have in its mature state. Besides, the subplacenta is already highly folded. These characteristics are adequate to sustain the development of future precocial offspring. The mesoplacenta, a structure present in other hystricognaths and related to uterine regeneration is described for the first time in this species. This detailed description of the placental and embryonic structure contributes to the knowledge of the reproductive and developmental biology of the viscacha, as well as that of hystricognaths. These characteristics will allow testing other hypotheses related to the morphology and physiology of the placenta and subplacenta, and their relationship with the growth and development of precocial offspring in Hystricognathi.
兔形目（啮齿目下的一个亚目）中的各种物种在繁殖方面具有高度特化的特点，这在啮齿目动物中是非常独特的。这些特点包括：较长的妊娠期、后代出生时具有极高的早熟性，以及较短的哺乳期。本研究描述了平原兔（Lagostomus maximus）交配后 46 天的可存活着床部位（IS）的胚胎-胎盘关系。本文中记录的观察结果与其他的鳞尾松鼠目和真兽类动物进行了比较讨论。在这个胚胎发育阶段，胚胎与其他真兽类动物相似。此时，胎盘的大小、形状和组织与成熟状态下的胎盘相似。此外，子胎盘已经高度折叠。这些特征足以支持未来早熟后代的发育。中胎盘是一种存在于其他鳞尾松鼠目动物中的结构，与子宫再生有关，在该物种中首次被描述。这种对胎盘和胚胎结构的详细描述有助于了解兔形目动物以及鳞尾松鼠目动物的生殖和发育生物学。这些特征将允许对胎盘和子胎盘的形态和生理学及其与早熟后代生长和发育的关系进行其他假说的测试。
