Histopathological Changes in Gills and Liver of African Catfish Clarias gariepinus Exposed to Methanolic Leaf Extract of Khaya senegalensis (African Mahogany)

Abstract

The histopathological changes in gills and liver of Clarias gariepinus juveniles exposed to methanolic leaf extract of Khaya senegalensis were investigated. Methanolic leaf extract of K. senegalensis was obtained, dissolved and dispersed into twelve (12) glass experimental aquaria with dimension 30.50 x 30.50 x 44.25 cm each containing 20 L of dechlorinated water of ten (10) fish per aquarium at different concentrations and three replicates. Juvenile C. gariepinus of weight 18.47±3.06 g and standard length 10.9±2.7 cm were introduced in each aquarium and exposed for 96 h period as endpoint toxicity. Three of these fish juveniles were randomly sampled from the control and each treatment aquarium and dissected to remove the gills and liver for histopathological analysis. The results showed a significant (P<0.05) association between the concentration of leaf extract K. senegalensis and mortality in exposed fish. The lethal concentration of the extract was 199.69 mgL^-1. The extract caused severe gills alteration, epithelial hyperplasia, cellular infiltration and mild fatty desquamation in the gills and high congestion, necrosis and desquamation of the liver. This plant is to be regarded as a piscicidal toxicant and should be considered unwanted alongside aquatic ecosystem.

Keywords: Toxicity, deformities, histopathology, Khaya senegalensis, Clarias gariepinus