Intensive aquaculture characterized by t he use of synthetic chemicals as growth promoters and immune boosters impacts negatively on the aquatic environment and also raises human health concerns, hence a need for organic alternatives. T his study investigates the effect of extract of Monodora myristica as a growth promoter, immune booster and gut area modifier in Clarias gariepinus. Crude extract was obtained from finely ground dry seeds of Monodora myristica using a standard procedure. A 40% crude protein diet was formulated and the crude extract was added at 0.0 (M0), 0.5 (M1), 1.0 (M2), 1.5 (M3), and 2.0% (M4). Diets were fed to triplicate groups of Clarias gariepinus (2.32g ± 0.03g) randomly allotted to fifteen plastic tanks at twenty fish per tank for 84 days. Growth and nutrient conversion did not vary significantly (p>0.05) across treatments. Increased villi width and cryptal width were recorded in fish fed Monodora myristica . Extract caused a significant increase (p<0.05) in the recorded values for Packed cell volume, hemoglobin and platelets this group. Anti-oxidative and immune responses were improved with M. myristica inclusion in diets as total protein, glutathione peroxidase, glutathione and glutathione S-transferase significantly increased (p < 0.05). This study showed improved absorption area and enhanced immune system with the inclusion of M. myristica extract in the diet of Clarias gariepinus .
Keywords: Nutmeg, Catfish, health status, growth and oxidative biomarkers.