BIOCHEMICAL AND MOLECULAR ALTERATIONS IN THE GILLS OF FRESHWATER FISH Oreochromis mossambicus EXPOSED TO TANNERY EFFLUENT

The present study was to find out the effects of tannery effluent on the fingerlings of freshwater fish Oreochromis mossambicus. The fishes were maintained at 10% concentration of tannery effluent in laboratory conditions for 30 days based on the lethal concentration studies. The gill tissue of the fishes was chosen for this study. Spectrophotometric analysis revealed a decline in total protein, DNA and RNA contents of the gills was statistically significant after exposure of the fishes to tannery effluent probable due to stress factors. Difference in intensity of genomic DNA between 750 and 1000bp was observed in the gill tissue in fishes exposed to tannery effluent, when DNA was subjected to agarose gel electrophoresis separation. Protein subunit separation by SDS-PAGE show high and low intensities in the protein bands obtained from the gills in the control and experimental fishes. DNA damage in the gills was confirmed by an increase in DNA damage by tail migration and by increase in percentage of mean DNA comet tail length formation.