WWW.WAS.ORG • WORLD AQUACULTURE • SEPTEMBER 2016 19 Overview Antarctic krill Euphausia superba is one of the most abundant species on earth, with an estimated biomass of around 500 million tons. They are shrimp-like in appearance, with an average body length of only 5 cm, with big black eyes and a reddish, semitransparent shell (Fig. 1). They live in huge swarms in the icy cold waters of the Southern Ocean, where they are harvested from the wild. The Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) restricts harvesting to a specific region in the Southern Ocean (Area 48) and to an annual krill harvest of 1 percent of the total biomass. (The precautionary level for other fisheries is 10 percent of the total biomass.) Aker BioMarine’s krill fishery has been certified by the Marine Stewardship Council as sustainable and 100 percent traceable. Krill meal is prepared from an aqueous extract of ground whole Antarctic krill that is cooked and dried, resulting in a brownish-orange powder containing around 60 percent protein with a nutritionally well-balanced amino acid profile (Fig. 2). Krill meal is a sustainable source of protein, omega-3 phospholipids, feed attractants and astaxanthin. The beneficial effects of incorporating krill meal into shrimp diets are reviewed in this article. Krill Meal for Shrimp Aquaculture Commercial shrimp farming has grown steadily to contribute almost two-thirds of the world’s marine shrimp production. Farming concentrates on penaeid shrimp, mainly black tiger shrimp Penaeus monodon and whiteleg shrimp Litopenaeus vannamei, known for their good adaptation to confinement and rapid growth (Fig. 3). Continued growth of shrimp farming and the change from low-intensity, small-scale to high-intensity, commercial farming (Fig. 4) has increased the need for sustainable protein sources in shrimp feeds. However, fishmeal supplies from wild-caught forage fisheries are not likely to increase from the current harvest level (Fig. 5). One way to address the high demand for fishmeal has been to replace it in shrimp feeds with soybean meal, which increases Benefits of Including Krill Meal in Shrimp Diets Lena Burri and Alberto J. P. Nunes (CONTINUED ON PAGE 20) FIGURE 1. Antarctic krill Euphausia superba. FIGURE 2. Krill meal (QRILLTM) composition has a high content of protein, omega-3 phospholipids and astaxanthin. Abbreviations: DHA, docosahexaenoic acid; EPA, eicosapentaenoic acid; n-3 PUFAs, omega-3 polyunsaturated fatty acids; TMAO, trimethylamine oxide. FIGURE 3. Litopenaeus vannamei (left) and Penaeus monodon (right).
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