Towards sustainable feeds for abalone culture: Evaluating the use of mixed species seaweed meal in formulated feeds for the Japanese abalone, Haliotis discus hannai

Abstract

Given the growing importance of the aquaculture sector in contributing to global seafood production, there needs to be a concerted effort to develop commercially relevant and ecologically sustainable feeds for the cultivation of commercially important species. Limitations on the availability and use of fish meal through EU directives (EC Regulation 999/2001 & EC Regulation 183/2005) are focussing research efforts to find alternative sources of protein for aquaculture feeds. Marine algae, although low in protein, are widely being considered as a potential alternative to fish meal as not only do they have the potential to impart additional health benefits when ingested but they can also be cultured under enrichment conditions to enhance their nutritional profile as a feed additive. For abalone (a marine gastropod mollusc), several studies have highlighted the benefits of a diet of fresh mixed species seaweed for cultivation. However, the performance of a mixed species marine algae meal, consisting of Laminaria digitata meal, Palmaria palmata meal and Ulva lactuca meal, in a formulated diet for abalone has not apparently been investigated. In this study, the performance of five novel, isonitrogenous, konjac glucomannan–xanthan gum (KX) bound feeds for the abalone Haliotis discus hannai were evaluated in a 12-week experimental growth trial. Comparisons were made between a basal diet formulation (Diet A), a basal diet+lipids+choline chloride (Diet B) and diets containing mixed sea…