) and best food conversion ratio (2.87±0.26) were obtained in fish fed 0.5 g 100 g −1 C. odorata leaf extract powder diet treatment. There were significant differences in fish carcass protein, lipid or ash content among the treatments (p<0.05). No differences occurred in white blood cells among the treatments (p>0.05) but there were greater improvement in the white blood cells of fish fed on dietary C. odorata leaf extract powder compared to the fish fed the control diet. The results suggest that dietary supplementation with C. odorata leaf extract powder improved growth rate, feed utilization, white blood cells and survival of C. gariepinus fingerlings.

This work was conducted to study the effect of diets supplemented with different levels of aqueous extract of siamweed (Chromolaena odorata) leaf powder on growth performance, feed utilization and some blood parameters of African catfish (Clarias gariepinus) fingerlings in 2014 at the Federal University of Technology, Nigeria. Fingerlings of about 6.84-6.86 g were fed diets supplemented with four concentrations (0.5, 1.0, 1.5 and 2.0 g) of C. odorata leaf extract powder for eight weeks. The highest specific growth rate (0.96±1.16 % day–1) and best food conversion ratio (2.87±0.26) were obtained in fish fed 0.5 g 100 g−1 C. odorata leaf extract powder diet treatment. There were significant differences in fish carcass protein, lipid or ash content among the treatments (p<0.05). No differences occurred in white blood cells among the treatments (p>0.05) but there were greater improvement in the white blood cells of fish fed on dietary C. odorata leaf extract powder compared to the fish fed the control diet. The results suggest that dietary supplementation with C. odorata leaf extract powder improved growth rate, feed utilization, white blood cells and survival of C. gariepinus fingerlings.