A method of economic comparisons for aquaculture diet development

The benefits that can result from substituting non-living feeds for living feeds in the diets of aquatic animals include improved reliability of the food supply, predictability of diet composition and reduced feed cost. Experimental feeds or supplements will only be used for commercial production of aquatic animals if there is an expectation of increased profit. Many experimental diets are not transferred to commercial use, however, because there is no standard method for aquaculture nutritionists to evaluate relative profitabilities of new diets. We developed a model to assess the profitability of experimental diets, based on economic equations and experimentally determined values for feeding cost, growth rate, growth efficiency and mortality. The model was tested by examining the economic feasibility of substituting yeast for algae in diets for the hard clam, Mercenaria mercenaria (L.), and by examining literature data for feeding studies with carp, Cyprinus carpio L.