Effects of Sub-lethal Concentration of Aqueous Extracts of Thorn Apple (<i>Datura stramonium</i>) Leaves on Weight Changes and Haematology Parameters of Fingerlings <i>Clarias gariepinus</i>

Abstract

Effects of acute and sub-lethal concentration of Datura stramonium on growth and some haematological indices on fingerlings of Clarias gariepinus were investigated. Acute lethal toxicity (LC₅₀) of D. stramonium leaves extracts for 48 hours exposures of C. gariepinus were determined at 0.2 ml/L. Clarias gariepinus fingerlings (4.22±0.01g) were exposed to D. stramonium at 0.00, 0.002, 0.02 and 0.2 ml/L for 28 days
and 10 days withdrawal. Each treatment was stocked 20 fish per replicate and replicated twice. Growth indices, haematological parameters, and histology were determined. The result shows a general increase within the weight
gain among the treatments but the value decreases as the concentration of D. stramonium increases. The haematological response to D. stramonium exposures was very variable relative to the exposed concentration. The
result obtained after 10 days withdrawal of haematology was relatively almost like the values obtained within the control and before the experiment. Histology revealed the gills, liver and intestines of C. gariepinus for the control shows no lesions, while the exposed groups recorded like moderate lamellar atrophy, and moderate diffuse hepatocellular degeneration. The results indicate that the exposure to sub-lethal levels of D. stramonium impacted on the growth, blood profiles, and histology of the exposed fish.