Anatomy of the digestive tube of sea turtles (Reptilia: Testudines)

Abstract

This study characterized the morphology of the digestive tube of five species of sea turtles. We used specimens found dead along the coast of the state Rio Grande do Norte, as well as specimens accidentally killed as a result of pelagic longline fishing. Nineteen animals of the following species were analyzed: Chelonia mydas (Linnaeus, 1758) (n = 9), Lepidochelys olivacea (Eschscholtz, 1829) (n = 6), Caretta caretta (Linnaeus, 1758) (n = 2), Eretmochelys imbricate (Linnaeus, 1766) (n = 1) and Dermochelys coriacea (Vandelli, 1761) (n = 1). After opening the plastron, we removed the digestive organs and described the external and internal morphology of each organ. The esophagus of all species had pointed papillae on the mucosa. The stomach varied in shape among species. Differences were found in the mucosa of the small intestine. It was reticular in the duodenum, and longitudinal rectilinear in the jejunum/ileum. In all species an alternation of saccular and narrow regions was observed in the large intestine. The exception was D. coriacea, in which the mucosa of the entire large intestine had irregularly distributed folds. The pattern of the esophagus was the same in all species. The morphology of the stomach differed among species, and these differences reflect their diets. In addition, the distribution pattern of the folds on the mucosa of the small intestine varied between regions of the intestine and among species. © 2011 Sociedade Brasileira de Zoologia.