Over the past twenty years, much success has been realized in the efforts to reduce the amount of fish meal in aquafeeeds in favor of other feedstuffs. Demand of fish meal as a principal source of protein has decreased due to many successful achievements, but is poised to increase as attention is being directed to the farming of more carnivorous species. A variety of approaches to achieve total substitution or reduction exist and are influenced by feeding habits and whether indirect sources of nutrients can be effectively coordinated into farming practices to meet protein requirements.
The ideal fish meal substitution is a high protein content, sustainable feedstuff that supplies essential amino acids qualitatively, quantitatively, and in the proper proportions, using lysine as a reference essential amino acid. The goal is to avoid providing excessive amounts of a protein source as a strategy to meet the requirements of essential amino acids. The energy to process potential feedstuffs to principally replace fish meal should minimally contribute to the environmental footprint and be cost-effective. Strategies to replace fishmeal and characteristics for evaluating potential are presented.