Identification of the tributary branches of the hepatic portal vein in the common sloth, Bradypus variegatus Schinz, 1825 (Pilosa: Bradypodidae)

[Identificação dos ramos tributários da veia porta hepática na preguiça-comum, Bradypus variegatus Schinz, 1825 (Pilosa: Bradypodidae)]

ABSTRACT

Bradypus variegatus, the common sloth, belongs to the Bradypodidae family, being considered a biological model to be applied in multidisciplinary research. This study was developed with the aim of being applied to clinical medicine and to the adequate management of the common sloth. Ten sloths were utilized, obtained post-natural death. The animals were fixed and to obtain the results, they were submitted to the dissection technique. For 80% of the animals, the portal vein originated from five tributaries, which were: the resulting vein from the anastomosis of the cardia vein, fundic vein, and the pyloric branches; the mesenteric trunk; the vein formed by the confluence of the stomach body branches and the cranial portion of the cavity of the cardia; the pyloric vein and splenic vein. While in 20% of the animals, the portal vein was comprised of six tributaries, because the fundic vein and cardia vein form two direct anastomoses, arriving at the portal vein two tributary vessels. This pattern differs in number and arrangement of branches when compared to the main domestic species. Therefore, the hepatic portal system is responsible for the drainage of the stomach, spleen, pancreas and intestines.

Keywords: Blood vessels; vascularization; liver; venal drainage; hepatic portal system