Descrição anatômica da artéria carótida externa e seus ramos na preguiça-comum, Bradypus variegatus Schinz, 1825 (Mammalia: Pilosa)

Abstract

Bradypus variegatus is a species of the family Bradypodidae and superorder Xenarthra, with a peculiar life habit and does not largely occur in quantity around the world as Brazil. It should be considered as a multidisciplinary biological model, making possible the maintenance of several biological studies. Particularly emphasizing the importance of morphological research, since these animals present great anatomical variation, mainly in the arterial vascularization. Thus, an anatomical description of sloth B. variegatus was performed from the external carotid artery (a.) and its branches. The corpses were acquired through the Wild Screening Center CETAS/IBAMA. Procedures were authorized by Animal Use and Experimentation Ethic Committee CEUA/UFRPE license nº 034/2015. Ten adult animals, all females, were sampled and submitted to dissection, then it was verified that the common carotid a. bifurcates over the external and internal carotid at the level of first tracheal ring. The external carotid extends to the maxilla, where creates branches to the temporal region and eye posterior pole. For all sampled animals, seven principal branches of external carotid were observed, and according to their origin and location were denominated as auricular, lingual, facial, bottom alveolar, temporal, maxillary and ophthalmic arteries. The maxillary and ophthalmic branches correspond to the terminals and others are lateral branches. In 50% of the animals sampled, the presence of arterial anastomoses was verified and 40% of them presented the addition of a branch to the principal. Almost one third (30%) of these demonstrated the presence of a tracheal branch and 10% of a sublingual branch, being these lateral branches. This study corroborates the understanding about the head and neck vascularization of sloth, aiding in the medical clinic of these animals.