Biochemical and Morphological Responses in Amazon Fish, Piaractus brachypomus Exposed To 2,4-D + Picloram Herbicide

Abstract

Pesticides as herbicides present an elevated potential for contaminating the aquatic environment, being able to create negative effects for organisms that are not the target, like fish. We evaluated the morphology and function of the hepatic, branchial and renal tissue on Piaractus brachypomus exposed to the herbicide based on 2,4-D + Picloram. Fishes were exposed to a sublethal concentration of the herbicide Norton® (1.1 g L-1, corresponding to 420 mg L-1 of 2,4D and 100 mg L-1 of picloram) for 96 h. After exposure, the plasma, gills, liver, kidney and white muscle were sampled for biochemical and morphological analyses. Acute exposure induced an increase on plasmatic glucose and decrease of muscular glycogen, while the plasmatic protein was also decreased. Tissues GST-GSH enzymatic biotransformation pathway and lipid peroxidation (LPO) were unchanged after acute exposure. Histopathological indexes analysis showed alterations on gills, liver and kidney which was evidenced morphofunctional damage by histopathological organ indexes. The results demonstrate that the herbicide induce different organs responses characterized by morphological and metabolic alterations on P. brachypomus. The adjustments of energy demand and gill, liver and kidney morphological changes produced by Norton® may affect the capacity of vital functions and capacity for development and reproduction of the specie.