Intensification and expansion of culture systems in aquaculture have been adapted to meet the increasing demand for fish protein and address diminishing marine fish catch. However, aquaculture is dependent on fish proteins and fish meal is primarily utilized as a major source of protein in diet formulati ons. Fish meal dependence remains critical for the growth and physiological development of the species being cultured. With its increasing demand, a decline in its production as well as increasing cost was observed. Previous studies have opted for alternative feed sources and the utilization of insects as feed ingredients attracted the most attention for its sustainability and ease of production. In the present study, rice moth meal was utilized which only maximizes by-products of the rice milling industry, specifically rice bran. Thus, this study was conducted to determine the growth and nutrient retention of juvenile tilapia fed with dietary rice moth meal as fish meal replacement.
An 8-week experiment was conducted evaluating the growth performance, feed utilization, and nutrient retention of juvenile tilapia fed with varying levels of dietary rice moth meal as fish meal replacement. The growth trial was done in a completely randomized design with four replicates for each treatment (5 treatments x 4 replicates x 20 fish p er tank). Five iso -nitrogenous and iso-lipidic formulated diets with four RMM replacement levels (at 25%, 50%, 75%, and 100%) replacing fish meal (by weight) were fed to Nile tilapia juvenile. Results showed t hat RMM could replace FM by up to 7 5% without a significant reduction in growth. However, 25% RMM replacement has growth promotion compared to the control. Weight gain and specific growth rate showed no significant differences between the control and the treated diets (25%, 50%, and 75% RMM replacement) while significa ntly decreasing in 100% RMM replacement (p<0.05). Protein retention efficiency, protein, and lipid retention efficiency tend to decrease with increasing replacement of RMM, however, 25% RMM replacement level reported a higher protein and lipid retention efficiency compared to the control. Moisture, protein, lipid, and ash in carcass composition did not differ significantly in all treatments (p>0.05). High survival was observed in all treatments and feed intake showed no significant difference among treatments. The amino acid composition of RMM suggests valine and leucine as the limiting amino acid with chemical scores of 26.36 and 26.76, respectively. Tryptophan, an essential amino acid, was not detected in RMM. Results of the study showed that rice moth meal can replace fish meal up to 75% in the diet of tilapia without compromising effects on growth and feed utilization. However, 25% RMM replacement promotes better growth compared to the control.