EFFICACY OF Ocimum gratissimum (SCENT LEAF) POWDER AS ANAESTHETIC AND ITS EFFECT ON THE HAEMATOLOGY OF Clarias gariepinus JUVENILES

Intensive nature of aquaculture have subjected farmed fish to a number of stressors due to handling proceedures and transportation from hatcheries to final stages. These stressors have most often been responsible for high mortalities recorded, hence hindering the growth of fish farming. Anaesthetics are used in aquaculture, fisheries and biological researches, as a way to minimize hypermotility during handling and transportation to reduce stress and mortality. Previous studies have reported the use of some plant materials to anaesthetized various fish species including C. gariepinus  This studies aimed to investigates the efficacy of Ocimum gratissimum as anaethetic and determine its effects on  some haematological parameters of C. gariepinus juveniles.   

Fresh leafs of O. gratissimum were obtained from within the university campus, identified, air dry for 5 days and blended to powder. The experimental treatment were prepared from a stock solution of 2g in 10 litres of water (200mg/l) into five concentrations (0, 50, 100, 150 and 200mg/l) in 20 litres of water. Stages of induction and recovery were monitored and recorded using a stop watch. Blood was ollected by severing the caudal peduncle into Ethylene Diamine Tetra acetic Acids (EDTA) for the analysis of various hemaetological parameters using standard methods.

The result revealed that O. gratissimum caused anaesthesia which was concentration dependent.  Induction time (min) reduced with increase in concentration while recovery increases as induction time reduces (Table 1 and Figure 1).