Sublethal effects of Quinalphos on haematology of Oreochromis mossambicus

Pesticide production and usage are inseparable from modern agricultural practices, posing detrimental ecological consequences. Fishes are sensitive bioindicators of aquatic environments, and the intensity of susceptibility of fish to xenobiotics depends on the fish species, the concentration of the toxicant, and the duration of exposure. The present work was aimed at providing a detailed study of the hematology of Oreochromis mossambicus exposed to three different concentrations of quinalphos and a control for 10, 20, and 30 days. The hematological parameters exhibited alterations compared to the control, indicating a direct or indirect effect of quinalphos on hematological parameters. Total erythrocyte count showed a 2.73% reduction, hemoglobin 15.03%, and packed cell volume 12.90% decreased with an increase in the concentration of quinalphos and duration of exposure. The absolute values of MCV showed 6.68%, MCH 8.29%, and MCHC also decreased 2.43%. White blood cell counts show an increased concentration with increasing quinalphos concentration compared to the control. The increase in WBC is 8.37% during exposure. The changes in hematological parameters observed on exposure to quinalphos may be attributed to the nonspecific defense mechanism of the fish against the stress induced by quinalphos through stimulation of erythropoiesis or alterations in metabolic activities.