Histological and physiological biomarkers to assess fish health in Londrina streams, state of Paraná

Abstract

Two fish species, known as lambaris (Astyanax altiparannae and A. fasciatus) were collected from the following streams in Londrina: Cambé (lake Igapó IV), Três Bocas, Apertados and Capivara. After capture blood samples and gills were immediately removed. Gills were fixed in Bouin and processed for light microscopy. A small amount of blood was used for hemoglobin determination and sodium and glucose plasma concentrations were determined after blood centrifugation. Animals from Cambé and Capivara streams showed certain severe histopathological alterations, such as lamellar aneurism and epithelial lifting. These fish also showed higher blood sodium concentration and a reduction of blood glucose when compared to fish from Três Bocas stream. Fish from Capivara showed a decrease in hemoglobin content when compared to animals from Cambé stream. Higher incidence of histological and physiological alterations observed in fish from Cambé and Capivara stream clearly indicates the animals’ health impairment