Six hundred sex-reversed male Nile tilapia (Oreochromis niloticus) fingerlings were used in a four month freshwater cage culture to demonstrate the utilization of a fish meal analog (FMA) as a replacement for Peruvian fish meal in tilapia diets. The control diet was formulated to contain 23% Peruvian fish meal. The FMA replaced 50% and 100% of the fishmeal on an equal weight basis (kg per kg) to make up the two remaining experimental diets.
No significant differences (P>0.05) were noted on the average weight gain and feed efficiency of tilapia fed the control diet (100% Peruvian fish meal) and those tilapia fed the 50% and 100% FMA based diets, respectively. A complete replacement of Peruvian fishmeal with FMA did not support acceptable fish performance. Although body measurements and feed efficiency were lower for tilapia fed the 100% analog based diet, these were not significantly different from those fed the control and 50% FMA based diets, respectively. Based on this study, growth performance of tilapia is affected by the total absence of fishmeal in the diet. However, a 50% replacement of Peruvian fishmeal with FMA is a potential replacement value to minimize the use of fish meal in tilapia diets and, therefore, lower feed costs.