Vol. 2, Issue 3 (2017)
Toxic effects of trivalent and hexavalent chromium on histopathology of gills in freshwater carp fish Catla Catla
Author(s): Dr. P Ranganatham
Abstract: Chromium, the heavy metal is an industrial effluent; a water pollutant enters into the food chain of aquatic ecosystems responsible for changes in the structural and morphology of the organs of the biota such as the fresh water fishes. Catla catla, a fresh water teleost fish, fingerlings when exposed to different sublethal concentrations of chromium for a different periods 8, 16, 32 days of time brought changes in the structure and morphology of the osmatic organs such as gills. In trivalent chromium exposed fish, a few pathological changes were seen during the initial days of exposure and then structural reorganization observed in later days of exposure, whereas in hexavalent chromium exposed fish the gills exhibited conformational degenerative changes such as swellings at the base of secondary gill lamellae, hypertrophy, hyperplasia and necrosis etc., all these changes confirmed structural disruption by hexavalent chromium ions on prolonged exposure.