Abstract
The plant Acacia sinuata (Merr.) shows piscicidal properties. The economically important freshwater fishes (Labeo rohita, Catla catla and Cyprinus carpio) were exposed to sublethal concentration (75 ppm) of alcoholic extract of the leaves of Acacia sinuata for 96 hrs. The toxic compounds in the leaves of Acacia sinuata showed piscicidal properties and induced haemolysis and affected almost all haematological parameters. All the parameters in blood except E.S.R. were found to be decreased in all the fishes, while E.S.R. was increased after 96 hrs of intoxication. Comparatively, haemolytic activity was lowest in C. catla, and highest in L. rohita. The results have been discussed in relation to mortality, metabolic activity and behaviour of these fishes.