Abstract
This study aims to present the diagnosis of causa mortis obtained through the necropsy proceedings and histopathological analyzes of sea turtles rescued between October and December 2016 by the Beach Monitoring Project, Phase II from Saquarema (22°56'11''S, 42°29'36.496''W) to Paraty (23°22'3.295''S, 44°43'30.335''W), in the State of Rio de Janeiro, Brazil. The chelonians were found dead or alive during beach monitoring. During necropsy the organs were analyzed, collected and fixed in 10% formalin solution and processed according to classic histological techniques. The eggs were analyzed according to morphology.1 In total, 19 green turtles Chelonia mydas (mean curvilinear carapace length of 45.5±5.1, range 37 to 53) were classified into groups according to the final diagnosis of a cooperative analysis of necropsies and histopathological reports. These data were classified as: septicemia in 8 animals (42.1%), renal insufficiency in two (10.52%), cerebral edema in one (5.26%), hypovolemic shock in one (5.26%). The cause of death was not determined in 7 animals (36.84%) although the lesions were defined, it was not possible to identify the most significant cause of death. Spirorchidiosis was not the cause of death, but was considered an incidental infection.3 It was a frequent histopathological finding both in animals with and without the cause of death determined. Eggs of spirorchiids were found in all organ systems and in all groups. In animals where it was not possible to determine the cause of death, type 1 eggs were found in the small intestine, spleen, eyes, lungs, and adipose tissues. Additionally, eggs of type 1 and 3 were found in spleen and lungs. Eggs of type 3 were found only in the group that had the cause determined as septicemia. In general, the occurrence of these eggs was associated with a chronic inflammatory response with a giant cell and lymphocytic reaction. Although the present work is unprecedented in the Brazilian region, the occurrence of spirorchiids is reported in the Brazilian coast and its impact is still little studied in the Brazilian region. Septicemia is related to causes of deaths in sea turtles in different parts of the world2,7,8 and seems to be an important cause of death in the Brazilian region as well. One of the factors that calls attention is the presence of spirorchiids eggs associated with septicemia. Although it has not caused death in any case, we believe it is an incidental infection with great debilitating potential not only in cases of septicemia but also in cases where the cause of death was not determined.
Acknowledgements
Biological samples were obtained through the "Phase 2" beach monitoring project between the states of Rio de Janeiro, Brazil. This project is part of the requirements established by the federal environmental licensing process of the Brazilian Environmental Agency (IBAMA), for the exploration of oil and gas by PETROBRAS at the Santos Basin pre-salt province.
* Presenting author
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