10.22376/ijpbs.2019.10.1.p1-12 Volume 3 Issue 3 2012 (July - September) Studies were undertaken to record distillery effluent induced quantitative alterations in the nucleic acids (DNA & RNA) and protein during three principal phases of ovarian cycle (prespawning, spawning and post spawning) of lessThan i greaterThan Colisa fasciatus lessThan /i greaterThan , a tropical freshwater fish. Observation were recorded under three different concentrations of the distillery effluent after 30 days of exposure. Observations reveal that 5% effluent concentration could produce least significant alterations (P greaterThan 0.05) in the nucleic acids and protein content during any phase of ovarian cycle after 30 days of exposure. However, 10% and 20% distillery effluent concentration brought significant alterations in the nucleic acid (DNA & RNA ) as well as protein content in all the phases in ovarian cycle after 30 days of exposure of lessThan i greaterThan Colisa fasciatus lessThan /i greaterThan and was more pronounced under 20% effluent concentration . The declining trend in selected biochemical parameters was more pronounced during the spawning phase in comparison to the preparatory as well as post spawning phase of the ovarian cycle . Anuradha Shukla And J.P.Shukla Distillery effluent, Phases of Ovarian cycle (preparatory ,spawning, and post spawning) Colisa fasciatus , Nucleic acids (DNA & RNA) , Protein. 147-154