Optimizing dietary protein and energy utilization to improve production efficiency of tilapia in the Western United States

The overarching objective of our project revolves around the refinement of commercial diet formulations for tilapia reared intensively within the Western United States, an essential step given tilapia's status as one of the most widely farmed and consumed fish. The diet compositions predominantly designed for pond-cultured tilapia, where natural feed organisms contribute significantly to growth (30-50%), may not serve the requirements of intensively reared species optimally. Our methodology involves determining the ideal protein-to-energy dietary ratio for distinct size classes and species of tilapia along with exploring the potential impact of vitamin supplementation on improving growth indices at various protein-to-energy ratios. This strategy was then applied to on-site pilot trials, assessing potential diet formulations.

Our findings underline that in circumstances devoid of natural food sources, an increased level of dietary protein and lipids is crucial for optimized growth in juvenile tilapia. Interestingly, large specimens did not display similar results. By harnessing this knowledge, farmers can make informed decisions on appropriate diets to maximize juvenile fish growth and economize cost/gain during the growth-out phase of larger tilapia.

Objectives:

1. Identify the optimum dietary protein to energy ratio(s) in practical diets for two different size classes and species of tilapia
2. Evaluate the ability of vitamin supplementation to improve growth performance at different protein:energy ratios as well as further evaluating potential formulations identified by laboratory testing in a pilot-scale on-farm trial
3. Develop an integrated outreach program, including at least one WRAC Extension publication, to meet the stakeholders’ needs