Presença de herpesvírus associado ao fibropapiloma em tartarugas verdes (Chelonia mydas) da região de forrageamento de Angra dos Reis, R.J.

Abstract

The Brazilian coast is inhabited by five species of sea turtles (Tetrapoda, Chelonioidea), which use this territory as a breeding and feeding area. The preservation of these animals has been threatened by human activities, notably ocean pollution by solid waste and interactions with fishing artifacts. The coast of the State of Rio de Janeiro is considered of extreme importance for the conservation of sea turtles, either because it shelters the latitudinal bordering areas of reproduction, or several feeding areas spread along its entire coastline. This project aims to examine the viral variants of the fibropapilloma-associated chelonid alphaherpesvirus 5 (ChHV5) in the foraging area of Angra dos Reis (R.J.) region, in the period of 2013 to 2016. Tumor and healthy tissue samples were collected from 43 green turtles that had fibropapillomas and subjected to total genomic DNA extractions and PCR amplifications of a DNA polymerase (DNApol) gene fragment from the viral genome, using the sense and reverse primers, GTHV2 and GTHV3, respectively. The results indicated that the prevalence of fibropapillomatosis in green turtles from the feeding area of the region of Angra dos Reis (R.J.), in the period from 2013 to 2016, was 14.4% (58 turtles affected in 404 captured by the PROMONTAR-Angra program). No relationship was observed between the high temperature in the region where the Plant Effluent (Piraquara) is located and the higher incidence of fibropapillomatosis. It was observed that the amount of viral DNA from biopsied tumors (higher performance) and from healthy skin (lower performance) exhibited a wide variation regardless of the year, age or geographic location of collection, implying a role in the etiology of fibropapillomatosis, and may reflect the stage of tumor development. Two haplotypes were identified, corresponding to the viral variants of the ChHV5 herpesvirus, here called B7 (N=15, 71.4%), and B8 (N=6, 28.6%), in the 21 samples that were successful in amplification and sequencing. There was no significant difference in the occurrence of viral variants of herpesvirus in green turtles from Angra dos Reis (R.J.) and other breeding and foraging areas in Brazil.