Descrição morfológica do coração e dos vasos da base do jacaré-do-pantanal (Caiman yacare Daudin, 1802) proveniente de zoocriadouro

Abstract

RESUMO.-Com este estudo objetivou-se descrever os aspectos anatômicos e histológicos do coração do jacaré-do--pantanal (Caiman yacare), proveniente de zoocriadouro. Para tanto, estudou-se 13 exemplares da espécie, os quais foram perfundidos, conservados em solução de formaldeído a 10% e submetidos às técnicas anatômicas específi-cas. O coração foi separado e amostras foram colhidas e submetidas à avaliação histológica. Macroscopicamente o coração é tetracavitário, e além de dois átrios e dois ventrículos, apresenta uma estrutura denominada cone arterial, do qual emergem os vasos da base do coração. Foram identificadas duas aortas, direita e esquerda, sendo que a esquerda emerge do ventrículo direito e se comunica com o tronco sistêmico direito por meio do forame de Panizza. Histologicamente o coração possui epicárdio, miocárdio e endocárdio típicos. Concluímos que a histologia do coração, no jacaré-do-pantanal, é semelhante à de outras espécies de répteis. Contudo, anatomicamente apresenta particularidades importantes, as quais representam, possivelmente, adaptações que permitiram a perpetuação da espécie. The aim of this study was to describe anatomical and histological aspects of the heart of Caiman yacare from a crocodile breeding center. For this purpose, we have chosen and further studied 13 specimens which were perfused and preserved in a 10% formaldehyde solution and they were subjected to the specific anatomical techniques. The heart was separated and samples were collected and submitted to the specific histological procedures. Macroscopically, the heart is four-chambered and besides two atria and two ventricles, has a structure called arterial cone from which the large vessels of the heart emerge. Two aortas, left and right, were identified. The left aorta emerges from the right ventricle and communicates with the systemic trunk through the Foramen of Panizza. From a histological point of view, the heart is typically composed of epicardium, myocardium and endocardium. According to these observations, it is assumed that the histology of the heart of "Jacaré-do-Pantanal" is similar to other species of reptiles. However, there are some anatomic particularities, which possibly represent the adaptations allowing the perpetuation of the species.

Morphoquantitative evaluation of the heart of cutia (Dasyprocta agouti) and capybara (Hydrochoerus hydrochaeris)

“…In accordance with other rodents such as paca (Ávila et al, 2010), rat and mouse, the hearts of cutias and capybaras in the current study were elongated cone shaped, consisting of two atria and two right and left ventricles (tetracavitary) easily distinguishable; furthermore, similarity with that described in the literature in relation to domestic animals (Ciszek et al, 2007;Ávila et al, 2010;Dyce et al, 2010;Konig and Liebich, 2011;Silva et al, 2016), Pantanal alligators (Alves et al, 2016) and swine (Lelovas et al, 2014), especially as to the thickness of the left ventricular wall compared to the right.…”

Notes on the gross anatomy of the heart of the broad‐snouted caiman, Caiman latirostris (Daudin, 1802)

“…On the other hand, in Nile crocodiles (Crocodylus niloticus Laurenti, 1768), both subclavian arteries are present, and the common carotid branches from the left subclavian artery (Goodrich, 1930). This is also the case in yacare caimans (C. yacare) and spectacled caimans (C. crocodilus), which were interpreted as having both subclavian arteries branching from the truncus arteriosus, and the common carotid artery branching from the left subclavian artery (Alves et al, 2016;Axelsson et al, 1989).…”

“…This is also the case in yacare caimans ( C. yacare ) and spectacled caimans ( C . crocodilus ), which were interpreted as having both subclavian arteries branching from the truncus arteriosus, and the common carotid artery branching from the left subclavian artery (Alves et al., 2016; Axelsson et al., 1989). These authors consider that there is a common misinterpretation of the left subclavian artery as the common carotid artery.…”

“…yacare (Yacare caimans) by Alves et al. (2016) and in the heart of Alligator mississippiensis by Jensen et al. (2016).…”

“…Regarding the cardiovascular anatomy, most works about crocodilians have focused on American alligators ( Alligator mississippiensis (Daudin, 1802)) and saltwater crocodiles ( Crocodylus porosus Schneider, 1801) as model animals (Altimiras et al., 1998; Axelsson et al., 1997; Eme et al., 2009; Jensen et al., 2016). However, there are few data on the gross anatomy of the heart of caimans (Alves et al., 2016). The present study describes new data on the topography, morphology and morphometry of the heart of C. latirostris and represents the first attempt to understand the gross anatomy of part of the circulatory system of this species.…”