| Sumario: | As shrimp prices become more competitive and the profit margins declining, producers are looking to high valuemarkets for their products. Shrimp produced using organic or environmentally friendly production conditions havethe potential to bring in higher prices through market differentiation. However, if one is to develop productionschemes for such markets, one must also produce an organic feed or one that has minimal levels of marine proteinsand oils. In previous research we developed a practical diet formulation without fish meal but containing marinefish oil. Since supplies of fish oil are also limited, this work concentrated on replacement of the marine oil source aswell as the testing of an experimental organic diet. In the first experiment, fish oil in two of the diets was substitutedby oil originating from commercially produced algae containing approximately 50% oil. These diets as well as acommercial feed were offered to juvenile Litopenaeus vannamei (Boone, 1931) over a 15 week growth trial. At theconclusion of the growth trial, survival, final weight, and feed conversion ratio (FCR) were not significantlydifferent among treatments. In the second experiment, the diet previously tested using plant and algae oils wastested against a diet using only plant oils. To examine the potential of an organic diet, a practical diet usingprimarily organic ingredients was also tested. The three diets were tested in conjunction with a commercial controldiet over a 12-week growth period. At the conclusion of this trial, shrimp reared on the organic diet and the dietwithout algae oil supplements were significantly smaller than those offered the commercial control. This result ispresumably due to a lack of HUFA in the diets without algae oils high in DHA and AA. To further test the potentialof a feed without fish meal, a commercial version of one of the test diets was produced at a feed mill and testedunder pond production conditions. As this was only a demonstration, statistical differences cannot be determinedbut the feed did appear to produce acceptable results under commercial pond production conditions. Based on theresults of these studies, it would appear that both fish meal and marine oil sources can be removed from shrimpfeeds if suitable alternative sources of protein and lipids are provided to meet essential amino acid and fatty acidrequirements of the shrimp. Although this study confirms the biological feasibility of fish meal and fish oilreplacement at the densities tested, commercial application will require further analysis of relative costs andmarketing benefits of these technologies.
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