Abstract
This study was conducted to assess the potential use of maize gluten meal (MG) as a substitute protein source for the African catfish, Clarias gariepinus. Four experimental diets formulated with different substitution levels of MG (control 0, 25, 50 and 75%) for fish meal (LT94), were fed to African catfish. The African catfish that were fed the high inclusion levels of MG showed significant differences (p>0.05) in gwoth performance. Weight gain ranged from 86.73 g for the control group to 19.50 g for the high inclusion level group (75% MG); specific growth rate (SGR) ranged from 4.89 to 2.59; feed conversion ratio (FCR) ranged between 0.85 and1.58; and the apparent net protein utilisation (ANPU) values ranged from 51.53 to 25.32%. In all cases, significant lower performances were recorded in the 75% MG substitution group (p>0.05). Furthermore, liver glycogen increased with increasing MG levels. Further, histological examination of liver tissue revealed alterations in the hepatic structure associated with higher levels of MG. These data suggest that no more than 25% of fishmeal should be substituted with maize gluten meal under the conditions tested in this study.