Multi-biomarker responses in the subantarctic fish (Patagonotothen tessellata) to assess the impact of anthropic pollution in coastal waters of beagle channel

FERREIRA, M.F.; GENOVESE, G.; FERNANDEZ D; LO NOSTRO, F. L.

Manaus

Congreso; 11th International Symposium on Reproductive Physiology of Fish; 2018

IntroductionCompounds released into the environment by anthropogenic activities disrupt processes of reproduction and development. Ushuaia city (Tierra del Fuego, Argentina), is located over the coast of the Beagle Channel (54?48 ºS, 68?190ºW) and due to the fast and unplanned urban growth and tourist activities, this system receives several substances mainly from untreated sewage and industrial wastewaters. The black southern cod, Patagonotothen tessellata (Perciformes, Notothenidae) predominates in the intertidal zone of Patagonia, sub Antarctic, and Antarctic waters, and is widespread in the Beagle Channel. It possesses male parental care. This study aims to evaluate differential responses in the endemic fish P. tessellata in a multi-stressor context.MethodsAdult male fish and water samples were collected from five locations (three presumed polluted sites and two reference sites). A total of 33 animals were captured in autumn, winter and spring. Skin mucus and blood samples were taken before dissection. Somatic indexes were calculated. Testes were histologically analyzed and sex steroids, skin mucus and plasmatic proteins were measured. SDS-PAGE followed by Western blot using heterologous antiserum was done for the detection of vitellogenin (VTG). Water physicochemical and microbiological analysis were performed.Results and DiscussionMales collected from polluted sites had lower HSI and GSI than those from reference locations. Testes were characterized as unrestricted lobular type and no histopathology or intersex condition was identified. Contaminated males had significantly higher levels of estradiol than control males but no difference was found between seasons. Total plasma proteins showed a positive correlation with GSI whereas the opposite was observed with mucus proteins irrespective of the site. Plasmatic protein levels were higher in males from polluted sites, where VTG was detected. Water analysis revealed differences between sampling sites, with high solid residuals and sulphates in water from polluted locations.ConclusionThe anthropic activities negatively influence on the coastal environment of Ushuaia city, not only in the water quality but also in fish. The abnormal detection of VTG in blood and altered sex hormone levels in contaminated fish may impact parental behavior. The present study sets baseline data to further studies in this region and provides strong evidences of reproductive disruption due to xenobiotics exposure in the sub Antarctic fish Patagonotothen tessellata.