Histological Transmogrification in Organs of Heterobrachus bidorsalis (É. Geoffroy Saint-Hilaire, 1809) Juveniles Exposed To 2-[(Phosphonomethyl) amino] acetic acid - Abstract
Static bioassay was conducted to determine the 96h median lethal level (LC50) of 2-[(Phosphonomethyl) amino] acetic acid on Heterobranchus biborsalis juveniles (4.90
± 0.13 g and length of 5.02 ± 1.0 cm respectively) and to describe the histological changes in the gill and liver. LC50 of H. bidorsalis fingerlings was determined graphically
as 18.07 mg/ L-1. Fish displayed the following behaviors respiratory distress (hyperventilation), erratic swimming, jumping out of the tank at higher concentration, molting, discolouration, irregular operculum opening and tail beat frequencies, loss of reflex and settling of the experimental fish at the bottom of the aquaria at higher concentration. Also fish mortality at varying concentrations increased with increasing concentration of glyphosate herbicides. Histological examination revealed mild degeneration in the gill architecture, artropy of the filament artery, distorted lamellar epithelium, epithelia proliferation/erosion of gill filaments and lamellae and necrosis of the gill cells. The liver showed no noticeable lesion at lower concentration of 2-[(Phosphonomethyl) amino] acetic acid, slight degeneration and vacuolation of the hepatocyte, evidence of inflammation of the liver cells with cellular infiltration of hepatocellular parenchyma and evidence of fatty acid degeneration and severe hepatic damage as a result of hepatotoxicity of 2-[(Phosphonomethyl) amino] acetic acid.