Abstract:
A six-week experiment was carried out to test the effects of total (100%) and partial (50%)
replacement of fish meal in the diet of African catfish growers with black soldier fly (B) meal, yellow
mealworm (M) meal, and a 1:1 combination of both (BM) on the production and health of fish. A
total of 420 fish with an average initial body weight of 200 ± 0.5 g were randomly distributed in
triplicate to seven diet groups (C, B50, B100, M50, M100, BM50, and BM100, respectively). The growth
performance and feed utilization of fish fed with partial or total replacement levels of FM with B were
not significantly affected (p > 0.05) during the 6 weeks of feeding. In contrast, significant differences
were observed between the groups fed with a diet where FM was totally replaced with M meal
and the control in terms of final body weight, specific growth rate, feed conversion ratio, protein
efficiency ratio, and protein productive value. Among the blood plasma biochemistry parameters,
total cholesterol exhibited a significant difference (p = 0.007) between the M treatments and the control
diet. The fatty acid profile of the liver was changed with respect to the long-chain polyunsaturated
fatty acid content in all experimental groups. Parallel with this, the upregulation of elovl5 and fas
genes in liver was found in all experimental groups compared to the control. Overall, this study
shows that fish meal cannot be substituted with yellow mealworm meal in the practical diet of
African catfish without compromising the growth, health and feed utilization parameters
