Certain effect of Tannery effluents on histophysiology of importal vital organs of Clarias batrachus (Linn)

Mature specimens of Clarias batrachus were exposed to Ganga river water in Kanpur containing environment for 115 days duration, over which the observations were recorded on 30^th, 60^th, 90^th, 105th and finally 115^th day. The fish was maintained unfed. An average increase of 4.2 ± 0.35 cm in length and that of 5.2 ± 0.39 gm in weight were recorded and in the same period the liver was found to have lost its weight by 3259 ± 8.1 mg. About half of exposed specimens died during experiment, while remaining half were apparently sluggish. Control specimens gained 7.0 ± 0.13 cm in length and 9.6 ± 0.9 gm in weight, but their liver showed a decrease in their weight in a range of 3859 ± 7.4 mg. About 15% fishes died and 85% inactive. The index was initially based on comparison of data obtained on 0 (zero) days.