Abstract This study determined the comparative impact of Moringa oleifera and Carica papaya leaves powder on some life stages of clarias gariepinus. 2,400 fry of Clarias gariepinus fish from the same stock were randomly stocked at 200 fish per plastic aquaria at 3 treatment levels designated control (0.00), 0.10g/l, 0.20g/l , 0.30g/l each with 4 replicates representing the treatment levels. The experiment was carried out for 8 weeks. The result obtained respectively showed that after 2, 4 and 6 weeks culture period the highest survival rate: of fry in Moringa oleifera treated aquarium at 0.10g/l was 86.35%; of post fry was 60% and of fingerlings was 60% while with Carica papaya it was observed that the highest survival rates recorded at 2, 4 and 6 weeks were respectively 63.75% for fry, 57.00% for post fry and 57.00% for fingerlings at 0.20g/l when compared to the control (2 weeks – 37% survival; 4 weeks – 25% survival and 6 weeks – 20% survival). These leaves at their respective doses as prescribed by this research are therefore suitable for raising young fishes since it appears that the anti-oxidant content of these plants arrests the hydroxyl radicals within the water body which takes care of the oxidative stress generally responsible for high level mortality in fish breeding.
Keywords Moringa oleifera, Carica papaya, Hydroxyl radicals, Oxidative stress, Anti-oxidant.