Desenvolvimento placentário em quatis: evolução filogenética em carnívoros? / Placental development in quati: phylogenetic evolution in carnivores?

AUTOR(ES)
FONTE

IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia

DATA DE PUBLICAÇÃO

13/12/2011

RESUMO

The importance of preservation of brazilian wild species is based on knowledge of their distribution, behavior in the wild and in captivity, and the detailed description of their reproductive biology in order to perpetuate the specie. One of the main impacts of this study is the scientific details of the uterine environment versus the process of placentation and their evolutionary phylogenetic position in mammals. By this propose we described the carnivore Nasua nasua (coati) placental morphology, showing the placental barrier that delimits the characteristic phylogenetic evolution of this organ. We used four placentas from pregnant females, captured from Mangabeiras Park, Belo Horizonte, MG, (SISBIO license 21030-1) and CECRIMPAS, São João da Boa Vista, SP, bought appropriately regulated by IBAMA. The technique of hemi-ovariossalpingohisterectomia was used to catch the placentas. Four gestational sacs where fixed in 4% paraformaldehyde, uterous and ovaries were sectioned and fixed in 2.5% glutaraldehyde. The material was photographed for macroscopic description. All the gestational sac was described, layer by layer, [the fetal membranes (amnion, yolk sac, allantois) + (chorion and haemophagus organ) + endometrius] = placenta. The stain techniques of PEARLS, Masson\ s trichrome, periodic acid-Schiff (PAS) and hematoxylin-eosin (HE) were used for microscopic description of the material. Immunohistochemistry with cytokeratin and vimentin evidenced avascular structures and trophoblast. For further details of the placenta and membranes we used the scanning and transmission electron microscopy. By analyzing the placenta was viable to describe the macroscopic and microscopic components of placental formation and characterization in the coati. The macroscopy showed us that the placenta is formed by the fetal membranes zonary chorion, allantois, amnion and yolk sac with inverted \"T\" shape, in addition to present the haemophagus organ. With the structural analysis of the material was possible to classify the coatis placenta as as chorioallantoic, zonary, lamellar and endotheliochorial. The acquisition of the material restricted the number of techniques that could be used for a better understanding and characterization of the coati placenta. However, we successfully described the placenta of those animals, providing better data on the reproductive aspects of the species for future comparative of carnivore order researches.

ASSUNTO(S)

nasua nasua carnivores carnívoros placenta placenta nasua nasu

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