Histopathology of gills, kidney and liver of a Neotropical fish caged in an urban stream

Abstract

Histological changes in gills, kidney and liver were used to evaluate the health of the Neotropical fish species Prochilodus lineatus, subjected to in situ tests for 7 days in a disturbed urban stream and in a reference site, during winter and summer. In fish caged in the urban stream the most common lesions were epithelial lifting, hyperplasia and hypertrophy of the respiratory epithelium, lamellar fusion, and aneurysms in the gills; enlargement of the glomerulus, reduction of Bowman's space, occlusion of the tubular lumen, cloudy swelling and hyaline droplet degeneration in the kidneys; hepatocytes with hypertrophy, cytoplasmic and nuclear degeneration, melanomacrophage aggregates, bile stagnation and one case of focal necrosis in the liver. The lesions were comparatively most severe in the liver. Histopathology showed to be a very suitable biomarker for use in conjugation with the in situ test, because the seasonal variation did not interfere in the results and it was possible to differentiate the sites in the urban stream from the reference site.<br>Alterações histológicas nas brânquias, rim e fígado foram usadas para estudar a saúde da espécie neotropical de peixe Prochilodus lineatus, submetida a testes in situ por 7 dias em um ribeirão urbano contaminado e em um local de referência, durante o inverno e o verão. Nos peixes confinados no ribeirão urbano as lesões mais comumente encontradas foram elevação epitelial, hiperplasia e hipertrofia do epitélio respiratório, fusão lamelar e aneurismas, nas brânquias; aumento do glomérulo, redução do espaço de Bowman, oclusão da luz tubular, degeneração granular e degeneração hialina, no rim; hepatócitos hipertrofiados, degeneração citoplasmática e nuclear, agregados de melanomacrófagos, estagnação biliar e um caso de necrose focal, no fígado. As lesões foram comparativamente mais severas no fígado. A histopatologia mostrou ser um biomarcador muito apropriado quando usada conjuntamente com os testes in situ, porque parece não ter sofrido interferência da variação sazonal e permitiu diferenciar os locais estudados no ribeirão urbano do local de referência

Alteration of Gills and Liver Histological Structure of Cyprinus carpio L. Exposed to Leachate

“…Fusion and hyperplasia of the gill lamella can be triggered by the effects of the toxins that alter cell glycoproteins including mucus, thereby affecting the negative charge of the epithelium and thus supporting the adhesion to the adjacent lamella (Ferguson, 1989). Camargo & Martinez (2007) stated that change such as fusion secondary lamella is one example of a self-defense mechanism. Basically, the increase in the distance between external environment and blood, would be a barrier to the entry of excessive contaminants, but the distance change between the lamella can lead to reduced capability in capturing oxygen that can be transmitted by blood.…”

Ectocommensal and ectoparasites in goldfish Carassius auratus (Linnaeus, 1758) in farmed in the State of São Paulo

“…The gills are generally considered to be good indicators of water quality and a model for studies of environmental impacts on fish (CAMARGO & MARTINEZ, 2007). In this study, it became clear that the unfavorable environmental conditions within tanks promoted the presence of several parasites, especially because many of these parasites were saprophytes and normally live symbiotically with healthy fish.…”

HISTOPATOLOGI INSANG IKAN PATIN SIAM (Pangasius hypophthalmus) YANG TERINFESTASI TREMATODA MONOGENEA

“…Secara histopatologi, Camargo & Martinez (2007) mengemukakan bahwa proses pertahanan insang dari perlekatan parasit yang menggunakan anchor dapat mengakibatkan pendarahan. Reaksi pertahanan pada lamella menstimulasi pertumbuhan selepite lamella insang yang sangat cepat (hiperplasia) dan peningkatan dari sekresi mukus oleh sel-sel mukus (Gambar 3).…”