Life Sustainability of Grass Carp (Ctenopharyngodon idella) Fishes on Implication of Distillery Spentwash

Abstract

Management and conservation of grass-carp fishes was made with different concentration of primary treated spentwash (PTSW) (0.1% to 1.2%) in water. Spentwash was analyzed for its physico-chemical parameters. Fingerlings fishes (obtained from V.C. Farm, Mandya, Karnataka),  were divided into 13 groups (G1 to G13) of 10 each and keeping G1 as ‘control unit’, G2 to G13 were exposed   to different concentrations of primary treated  spentwash for a period of 6 days   in different aquariums of  36†x 15†x 18†size. It was found that all fishes behaved normally up to 1.1% spentwash, thereafter, they behaved abnormally and could not sustain for longer time and eventually died.  This is due to high BOD and COD, ammonical nitrogen and also due to the insufficient dissolved oxygen (DO) for natural respiration at higher concentration of spentwash.  The ‘mortality rate’ (MR) was 100% in G13 (1.2% spentwash) and 25.5% in G12 (1.1% spentwash) after 12 hr exposure, and in G2 to G11 MR was 0% even after exposure of 6 days.  Implication of distillery spentwash into water bodies at higher concentration results deleterious effect on the life of Grass Carp (Ctenopharyngodon idella) fishes.