Crustacean amphipods from marsh ponds: a nutritious feed resource with potential for application in integrated multi-trophic aquaculture

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Inglés. Coastal protection, nutrient cycling, erosion control, water purification, and carbonsequestration are ecosystem services provided by salt marshes. Additionally, salt pondsoffer coastal breeding and a nursery habitat for fishes and they provide abundantinvertebrates, such as amphipods, which are potentially useful as a resource inaquaculture. Fishmeal and fish oil are necessary food resources to support aquacultureof carnivorous species due to their omega-3 long-chain polyunsaturated fatty acids (n-3LC-PUFA). Currently, aquaculture depends on limited fisheries and feed with elevatedn-3 LC-PUFA levels, but the development of more sustainable food sources is necessary.Amphipods appear to be a potential high quality alternative feed resource for aquaculture. Hence, a nutritional study was carried out for several main amphipod species—Microdeutopus gryllotalpa, Monocorophium acherusicum, Gammarus insensibilis, Melitapalmata and Cymadusa filosa—in terrestrial ponds in the South of Spain. These speciesshowed high protein content (up to 40%), high n-3 PUFA and phospholipid levels,and high levels of phophatidylcholine (PC), phosphatidylethanolamine (PE) andtriacylglycerols (TAG), the latter being significantly high for M. acherusicum. M.gryllotalpa and M. acherusicum showed the highest proportion of lipids (19.15% and18.35%, respectively). Isoleucine, glycine and alanine were the dominant amino acidsin all species. In addition, amphipods collected from ponds showed low levels of heavymetals. Furthermore, the biochemical profiles of the five species of amphipods havebeen compared with other studied alternative prey. Therefore, pond amphipods aregood candidates to be used as feed, and are proposed as a new sustainable economicresource to be used in aquaculture. G. insensibilis may be the best for intensive cultureas an alternative feed resource because it shows: (1) adequate n-3 PUFA and PLcomposition; (2) high levels of glycine, alanine, tyrosine, isoleucine and lysine; (3) highnatural densities; (4) large body size (1 cm), and (5) high concentration of calcium.Moreover, a combined culture of amphipods and fishes in these marsh ponds seemsa promising and environmentally sustainable way to develop Integrate Multi-TrophicAquaculture (IMTA) in these ecosystems.