Placental development in the early stages of red-rumped agouti pregnancy (Dasyprocta leporina Linnaeus, 1758)

• Published in: Journal of veterinary science (Suwŏn-si, Korea) Korea), 2023, Vol.24 (5), p.1-15
• Main Authors: de Oliveira, Gleidson Benevides, de Araújo Júnior, Helio Noberto, de Moura, Carlos Eduardo Bezerra, Favaron, Phelipe Oliveira, Pereira, Alexsandra Fernandes, de Oliveira, Moacir Franco
• Format: Article
• Language: English
• Subjects: Original
• ISSN: 1229-845X; 1976-555X
• DOI: 10.4142/jvs.22323

BACKGROUNDHystricomorpha rodents display a similar placentation model to humans. The present study was carried out considering the scarcity of information concerning the placental development in agouti.OBJECTIVEDescribe the microscopy of the placenta, subplacenta and yolk sac of agoutis in early pregnancy and report on the inversion of the yolk sac.METHODSFifteen females between the 14th-32nd day of gestation were used following euthanasia. Gestational buttons were collected, fixed, processed, stained to optical microscopy or immunohistochemistry.RESULTSChorioallantoic placenta (CP) ranged from conical to a half-sphere, as follows: from the 14th to 17th day, the CP displays an inverted "V" shape, predominantly formed by cytotrophoblasts; from 20 to 22 days, formed almost entirely by cytotrophoblasts; at 28 days, a half sphere, with distinct lobes and interlobular area, numerous maternal gaps delimited by syncytiotrophoblasts and trophoblast giant cells; at 32 days, globose and undergoing the maturation process. Subplacenta, located between decidua and CP, initially presents septa consisting of simple columnar epithelium and after 17 days, comprising stratified epithelium. Visceral yolk sac (VYS) is attached to two CP projections between 14 and 17 days, formed by a simple cubic epithelium and inverted. Between 20 and 22 days, the epithelium displays apical villous projections with cytoplasmic vacuoles and a vascularized mesoderm. After the 24th day, the VYS near the placenta is pleated, very vascularized and villous, with decreased villi sizes further away from the placenta.CONCLUSIONThe agouti CP displays similar characteristics to other hystricomorpha, including placenta lobulation, a subplacenta and an inverted vitelline placenta.