Ultrasonographic characterization of implantations in a physiological embryonic death model: Lagostomus maximus (Mammalia, Rodentia, Histricongnathi)

FRANCISCO ACUÑA; GUADALUPE RANEA; CLAUDIO GUSTAVO BARBEITO; ENRIQUE LEO PORTIANSKY; MARÍA ANGÉLICA MIGLINO; MIRTA ALICIA FLAMINI

CABA

Congreso; Xth Meeting of the Latin American Society for Developmental Biology; 2019

Latin American Society for Developmental Biology

The plain viscacha Lagostomus maximus constitutes a model of physiological embryonic death due to the differential survival of its implantations. Of 10-12 implantations only 2 near the cervix will progress; the rest are reabsorbed by still unknown causes. In this work, implantations (i) of females with early pregnancy (first third of gestation) were characterized by ultrasound. After anesthesia, the gravid uterine horns (UH) of 3 females were analyzed with a linear transducer. The presence of 4i/UH was observed and identified as: i1, i2, i3 and i4 following the craniocaudal axis of the organ. The size of these implants increased from i1 to i4. Implants i1 to i3 were solid, echogenic and lacking an embryo, fluid and placenta (gestational vesicles in resorption). In contrast, the presence of a solid, echogenic and discoid structure (placenta) was observed in i4. Besides, a cavity filled with anechoic fluid containing an embryo with developed cephalic and caudal poles, absence of limbs and viscera was observed. The vascular Doppler determined the viability of this embryo due to cardiac activity. These preliminary data will allow to characterize the embryonic development of Lagostomus maximus and, in turn, to establish the moment in which physiological and sectorized embryonic death begins. In addition, it will allow morphological and molecular studies to understand embryonic differential survival in mammals, with emphasis on species of interest for veterinary medicine.