Dimethoate (30%EC) induced toxicities on the tissues of the Indian major carp: Labeo rohita (Hamilton)

Abstract

Organophosphorus pesticides are used extensively in the agricultural fields due to their rapid biodegradability and non-persistence to control the pest but their broad spectrum of harmful effects extends far beyond the pest. The present study is aimed to investigate the effects of sub-lethal doses of Dimethoate (30%EC) on brain, gill, liver and kidney of Labeo rohita. 96 hr LC50 is calculated by Probit Analysis and found to be 24.55 μl/L. Histological tissues are collected from both control and experimental groups after 10 days of pesticide exposure. Microtomy is used for histopathological studies and severe histological changes are found like in brain Dimethoate treatment drastically affected molecular and granular layers causing necrosis, in liver caused severe pathological lesions when compared to control, in kidney experimental group showed severe damage such as large space between tubules and tissue, shrunk, fragmented glomeruli with large Bowman’s space enlarged lumen and disintegrated, vacuolated renal tubules, in gills several degenerative changes is also observed and it is evident from the findings that Dimethoate is moderately toxic to fish.