Research Perspective on Biological Science Vol. 11

Haematological indices are important parameters to evaluate the general physiological status of fishes and may be considered as stress indicators for estimation of the response reactions of the fish to various environmental conditions. This chapter explores the impact of sago industry effluent on the blood characteristics of the freshwater fish Clarias batrachus, with emphasis on changes that occur during prolonged exposure. The continuous release of agro-industrial waste into aquatic environments has become a growing concern, particularly due to its potential effects on fish health. In this context, haematological parameters provide a practical and sensitive means of assessing physiological stress in aquatic organisms. In the present study, fish were maintained in different concentrations of sago effluent (0%, 25%, 50%, and 75%) for a period of 28 days under sublethal conditions. At the end of the exposure period, clear alterations in blood parameters were recorded. There was a gradual reduction in red blood cell count, haematocrit, mean corpuscular volume, and mean corpuscular haemoglobin as the effluent concentration increased. These changes point towards a reduced capacity for oxygen transport and possible interference with normal blood cell formation. On the other hand, an increase in white blood cell count was observed, which may reflect a defensive response to stress. Overall, the study indicates that sustained exposure to sago effluent can disrupt normal physiological functions in fish. The observed variations in blood indices highlight their usefulness as early indicators of environmental stress. The findings also stress the importance of effective treatment and management of industrial effluents to minimise their impact on aquatic ecosystems.