Impact of Different Concentration of Thorn Apple (Datura stramonium) Extract on Growth, Histopathology and Blood Profiles Response to Sub- Lethal Exposure of Nile Tilapia (Oreochromis niloticus) Juveniles

Abstract

This study investigated the toxic effects of Datura stramonium leaves extract on growth, histopathology and blood profiles of Oreochromis niloticus juveniles. Datura stramonium leaves extract of various concentrations were prepared at 0.00 (control), 0.002, 0.02 and 0.2 ml/L for 28 days and 10 days withdrawal in triplicate. Twenty (20) Oreochromis niloticus fingerlings (6.05±0.01g) were randomly distributed into each experimental bowl containing 45 L of treatment concentrations. Biological evaluation, blood profiles parameters, and histology of the exposed fish were determined. The result shows an increase within the weight gain and the weight gain was higher in the exposed groups expect TAL 4 than the control. There was no significant difference (P>0.05) among the treatments. The haematological response to D. stramonium exposures shows that the values of packed cell volume and haemoglobin were higher in the exposed groups compared to the control while the white blood cell, neutrophils, and lymphocytes decrease as the concentration of the plant increases and were lower than the control. The result revealed a higher value of total protein and albumin in the exposed groups compared to the control. There were decreased in the values of ALT and AST when compared to the control and the values of total protein, albumin, ALT and AST after 10 days of withdrawal show a similar trend in values obtained before the experiment. The result of histopathology shows no observable lesions were observed in control group while there were moderate alterations in gills, liver and the intestine of the exposed groups. This investigation revealed that continuous use of the D. stramonium leaves extract in the aquatic environment will affects the growth, blood profiles and histopathology of the exposed fish.