RESUMEN
ABSTRACT Light and scanning electron microscopic studies of erythrocytes of Channa punctata exposed to two sublethal doses of lindane over a period of 21 days revealed myriads of anomalies. High frequency of micronucleus appeared progressively in the erythrocyte, ranging from 3.8-7.5%, when monitored weekly for 21 d at 0.25 g/L and 1.0-3.0% at 0.025 g/L lindane. Prominent structural anomalies of erythrocytes included abnormal shapes, vacuolation, membrane invagination and disintegration. At higher dose and at later duration, a unique tendency of abnormal cells to stick together was observed. It could be concluded that commercial formulation of lindane could induce genotoxicity and structural anomalies in the erythrocytes of fish.
RESUMEN
Effects of three sub lethal concentrations of cadmium chloride (0.636, 0.063 and 0.006 mg l-1) on oxygen consumption and gill morphology in Indian flying barb, Esomus danricus (Hamilton-Buchanan), a teleost fish, were studied. When compared to control, 0.636 mg l-1 of cadmium chloride after 7, 14, 21 and 28 day exposure showed a significant decline in rates of oxygen consumption at 32.98, 28.40, 23.88 and 21.69 ml hr-1 100g-1 of tissue, respectively; while, 0.063 mg l-1 of cadmium chloride for the same exposure durations showed a significant decline in rates of oxygen consumption at 34.28, 29.30, 28.05 and 26.47 ml hr-1 100g-1 of tissue, respectively. However, significant decline in the rate of oxygen consumption at 0.006 mg l-1 of cadmium chloride could be observed from 21st day of exposure. Gill tissue showed various histopathological changes including epithelial lifting, hyperplasia, mucous secretion, marked leucocyte infiltration in the epithelium after 28 days of cadmium chloride exposure.