Producción CyT
Placenta - TERM PLACENTA OF THE SOUTH AMERICAN SEA LION, OTARIAFLAVESCENS (SHAW, 1800)
Congreso
Autoría:
Hernández R ; Diessler M ; GOMEZ CASTRO, MARÍA GIMENA ; Loza CM ; Loureiro JP ; Woudwyk M ; Scianda M ; Costa E ; Pergazere M ; Barbeito CFecha:
2022Editorial y Lugar de Edición:
W B SAUNDERS CO LTDResumen *
Objectives: To describe morphological features of the term placenta ofSouth American sea lion.Methods: Placentas from three sea lions that gave birth to normal puppieswere analyzed. Those mothers were born in Mundo Marino oceanarium,where they live in a controlled environment. The placentas were formalinfixedand processed by histologic techniques.Results: The placentas were zonary and belt-shaped. The surface facingthe uterus was irregular and rough, with bulging grayish-orange margins.A few 3-5 cm ovoid grey structures, scattered through the belt, protrudedfrom the fetal surface. Maternal and fetal structures formed a labyrinth inwhich the trophoblast, mostly syncytial, directly faced maternal vessels. Aprofusion of small fetal capillaries surroundedmaternal vessels, frequentlyindenting the syncytiotrophoblast. This arrangement resulted in a thinendotheliochorial barrier. Maternal vessels were larger towards the fetalaspect of the labyrinth, as the so-called “sinusoidal” vessels in other pinnipeds,and they had high endothelia in most areas. In junctional areas,tertiary chorionic villi were evident. They were partially laying free, closeto endometrial detritus in the uterine lumen, but focally anchored to theconnective uterine tissue through projections of syncytiotrophoblast. Themargins of the placenta were composed of folded chorionic villi surroundingabundant brilliant orange crystals. Similar folds delimited quitelarge areas of stagnant blood and necrotic tissue close to the pigmentedzones.Conclusion Regarding its zonary, belt-shaped, labyrinthine, and endotheliochorialnature, the Otariaflavescens placenta resembles that of mostcarnivores. Particularly, the “sinusoidal” maternal vessels, and the largequantities of crystals regarded as bilirubin, are hallmarks of pinnipedplacentas. Beyond the scarce, isolated, and mostly macroscopic data onCallorhinusursinus and Zalophuscalifornianus, most of the knowledgeabout pinniped placentas comes from Phocidae. Though, we cannotcompare the present findings to others in Otariidae. Up to our knowledge,this is the first description of Otariaflavescens placenta. Información suministrada por el agente en SIGEVAPalabras Clave
OTARIA FLAVESCENSSOUTH AMERICAN SEA LIONPLACENTA