MACRO AND MICROSCOPIC CHARACTERIZATION OF LANGUAGE AND ESOPHAGE OF SEALED TURTLES (TESTUDINES) IN RIO GRANDE DO NORTE COASTAL, BRAZIL
Gastrointestinal system. Histology. Stereology. Chelonian
There are currently seven known species of sea turtles in the world and all are at some level of threat of extinction. In this context, it can be considered that studies on the basic biology of these animals allow us to make important management decisions for conservation. There is still a lack of information that relates eating habits to the internal morphology of these animals. For this reason, the present work aims to characterize the macro and microscopic morphology of the tongue and esophagus of sea turtles, establishing comparisons between species and their eating habits. From January 2018 to November 2019, tongue and esophagus samples of stranded sea turtles that died or died at the Cetacean Costa Branca Rehabilitation Base were evaluated throughout the coast of Rio Grande do Norte and east coast of Ceará. The animals were necropsied and the organs of interest were dissected together and fixed in 10% formaldehyde. Subsequently, photographic recording, weighing and biometrics were performed and then the tongue samples were sent for histological cleavage and the esophageal samples for processing the stereological technique. As preliminary results, it is worth highlighting the unpublished histological findings regarding the sea turtle tongue. It has been observed that the dorsal surface is coated with keratinized stratified epithelium, with pointed projections in some portions and filiform shaped papillae. Below the keratin layer there was the presence of ducts. The lamina propria consisted of loose connective tissue with the presence of nerve plexuses and blood vessels. The tongue musculature is distributed in two orientations, longitudinal and circular. In C. mydas, glands were observed in the posterior region of the tongue, while in C. caretta, mucous cells in the epithelium, suggesting the secretion of mucus and saliva by the organ, probably assisting in chemical digestion.