Authors : G. Aligba, V.O. Ayuba and S.G. Solomon
Abstract: The acute toxicity of Checkmate®, a herbicide containing 720 g L–1 of 2,4-D amine (2,4-Dicholorophenoxyacetic acid) to juveniles of Clarias gariepinus of mean weight of 36.40±0.01 g and standard length of 17.91±0.21 cm were investigated under laboratory condition. In a static renewal bioassay, the fish were exposed to 0.00, 3.42, 3.76, 4.14, 4.50 and 4.86 mg L–1 of 2,4-D amine. The 96 hours lethal concentration (LC50) of 2,4-D amine to juvenile of Clarias gariepinus was 3.95 mg L–1. The fish exposed to 2,4-D amine showed toxicological signs of erratic swimming, loss of balance and air gulping before death during the acute bioassay. Histopathological changes in the gill architecture were characterized by lifting of epithelia layer, eroded gill filaments, necrosis of epithelial cells, hyperplasia and fusion of lamellar epithelial cells, hemorrhage and erosion of lamellae. There were evidence of ruptured hepatocytes, cellular infiltration and degeneration of the central vacoulation, haemorrhages, hypertrophy of hepatocytes, fibrosis and necrosis in the liver of fish exposed to 2,4-D amine. 2, 4-D amine is highly toxic and its use in or near aquatic environment should be monitored.
G. Aligba, V.O. Ayuba and S.G. Solomon, 2015. Acute Toxicity and Histopathological Effects of 2,4-D Amine on Gill and Liver of Clarias gariepinus Juvenile. Journal of Fisheries International, 10: 19-27.