“…This is in line with the hypothesis of Abbas () and Manjappa, Keshavanath, and Gangadhara () that nutrient utilization in a diet and its retention in fish carcass are related to both the dietary protein levels and the availability of non‐protein energy sources with a lower inclusion of dietary fiber. This finding is similar to earlier studies, where soybean meal was replaced by other plants in the practical diets of tropical fish species (Fagbenro, Adeparusi, & Jimoh, ; Azaza, Mensi et al, ; Azaza, Wassim et al., ; Tiamiyu, Okomoda, & Akpa, ). Some earlier studies revealed an insignificant effect of dietary soybean substitution (Lin, Mai, & Tan, ; Van Vo et al., ; Wang, Kong, Li, & Bureau, ), while others revealed a significant increase (Fagbenro et al., ; Okomoda, Tiamiyu, & Uma, ).…”