eng Science and Education Publishing Applied Ecology and Environmental Sciences 2328-3920 2021-05-30 9 5 575 579 10.12691/aees-9-5-8 AEES2021958 article N. Ganesan 1 K. Samyappan 1 R. Saravanan rsaravanan51283@yahoo.com 1 Department of Zoology, Dr Ambedkar Government Arts College, Vyasarpadi, Chennai 600039, Tamil Nadu, India The present study was designed to evaluate the effect of tannery effluent on the fingerlings of freshwater fish Oreochromis mossambicus. The fishes were maintained at 10% concentration of tannery effluent for a period of 30 days. Apoptosis was studied by activity of caspases. Caspase 3 and 9 activity showed significant alteration. DNA seperation by agarose gel electrophoresis shows difference in intensity of genomic DNA between 750-1000 bp in fishes exposed to tannery effluent. DNA damage was also confirmed by Comet assay which showed an increase in DNA damage and tail migration was indicated by increase in percentage of mean DNA comet tail length formation. http://pubs.sciepub.com/aees/9/5/8/aees-9-5-8.pdf Oreochromis mossambicus Tannery effluent Brain Caspases 3 and 9 Genomic DNA Comet assay