Pymetrozine Causes Physical, Haematological, Blood Biochemical and Histopathological Abnormalities in Bighead Carp (Aristichthys nobilis)

Abstract

Pymetrozine a synthetic insecticide, is widely used to control pests and insects in maize and other cereal crops. Pymetrozine may contaminate nearby aquatic ecosystems as a result of widespread and long-term use, causing harm to a variety of creatures. The residues of this pesticide can have devastating effects on various species, as well as public health, if they enter the food chain. Pymetrozine’s toxicity in freshwater fish was the main focus of the current study. For this reason, 80 fish were collected and placed separately in four groups of 20 fish each. Pymetrozine was given to fish in groups B, C, and D at doses of 500, 1000, and 1500 µg/L in water. For histopathological and hematological examinations, blood and other visceral tissues were obtained on days 10, 20, and 30 of treatments. Different physical and behavioral disorders were noted in terms of time and concentration manners. In comparison to control fish, the hematological profile including lymphocyte, hemoglobin erythrocyte and monocyte counts, was considerably (p < 0.05) lower. The final results on the serum biochemical parameters showed significantly (p < .05) higher concentrations of liver biochemical profile, biomarkers of kidneys, triglyceride, glucose, and cholesterol in fish treated with pesticide. Histopathological examination showed renal tubular degeneration, widening of Bowman’s space and necrosis in kidneys. Different histopathological lesions in liver of treated test specimens including edema, hemorrhages, atrophy of hepatocyte and hepatocyte having eccentric nuclei. In the brain, different histological alterations like necrosis and degeneration of neurons, and microgliosis were seen, whereas the heart of treated fish showed hemorrhages, edema, and neutrophilic myocarditis. In conclusion, Pymetrozine appears to have harmful effects on blood biochemistry and histological alterations in several tissues of bighead carp.