INCREASING COMPETITIVENESS OF SWEET LUPINE AND FABA BEAN IN FEED VALUE CHAINS IN EUROPE

Introduction

Although inclusion rates of fishmeal and fish oil have already been strongly reduced in aquadiets, they remain staple ingredients, and a main environmental and economic concern of aquaculture today (Schmidt et al. 2016). Terrestrial plant protein sources have been key to alternative feed protein but the main interest to date has been in soy products, which have come under public criticism due to the widespread use of transgenic seeds and deforestation for soy cultivation. Recent studies focus on additional terrestrial protein sources, mainly grain legumes like field pea, lupin and faba bean (Carter & Hauler, 2000; De Santis et al. 2015; Øverland et al. 2009), which are regionally and organically produced. Legumes provide nitrogen for themselves and subsequent plants (Blume, 2010; Sulieman, 2015) and thus reduce the overall fertilization needs during crop rotation. Here we present validated diets for 3 species relevant for European Aquaculture (Litopanaeus vannamei, Salmo salar, Dicentrarchus labrax) containing locally grown lupin and faba bean. The diets are formulated tightly aligned to the requirements of each species, which is necessary not only from the economic but also from the ecological point of view. These formulations and diets are valuable for producers aiming to make fed aquaculture of salmon, shrimp of seabass more sustainable in the future.

Material and Methods

Controlled feeding experiments have been conducted in a RAS device (8-12 weeks) with three species of high relevance for European aquaculture (L. vannamei, S. salar, D. labrax). Aquafeeds containing meal or protein concentrate of Blue lupin (Lupinus angustifolius Boregine) and Faba bean (Vicia faba) as fish meal and soy product replacement were formulated to accurately meet the species and stage nutritional requirements, i.e. equal energy content, protein and amino acid profile, lipid and fatty acid composition, vitamins and minerals. After an appropriate trial period, samples were taken for metabolic, histologic and immunological analyses.

Results and Discussion

Untreated lupine meal can be used as an alternative protein source at rates of up to 10% (-20%) of the total feed (= 30-40% of animal protein) without growth or metabolic impairment compared to a commercial shrimp feed (Fig. 1a, b). A moderate lupin inclusion obviously operated as bioactive compound stimulating the shrimp’s immune system (Fig. 1b, d).

Faba bean protein concentrate as well as Lupin protein concentrate can be used at rates of 35% of the total feed as a regional alternative to soy and as a partial fish meal replacement in feed for postsmolt Atlantic salmon without any impairments of health and growth (Fig. 2a).

Lupine kernel meal can be used in high inclusion rates (-50%) as a replacement for fishmeal in diets for the carnivorous European Seabass, with appropriate pre-treatment effectively mitigating negative effects on growth in smaller individuals (<30g) (Fig. 2b).

In conclusion, grain legumes and their products have great potential as a main protein source in diets for carnivorous aquaculture species in Europe.

This study is part of the project “TRansition paths to sUstainable legume-based systems in Europe” (TRUE), and it has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 727973.

References

Carter, C. G., & Hauler, R. C. (2000). Fish meal replacement by plant meals in extruded feeds for Atlantic salmon, Salmo salar L. Aquaculture, 185, 299-311.

De Santis, C., Crampton, V. O., Bicskei, B., & Tocher, D. R. (2015). Replacement of dietary soy- with air classified faba bean protein concentrate alters the hepatic transcriptome in Atlantic salmon (Salmo salar) parr. Comp Biochem Physiol Part D Genomics Proteomics, 16, 48-58. doi:10.1016/j.cbd.2015.07.005

Øverland, M., Sørensen, M., Storebakken, T., Penn, M., Krogdahl, Å., & Skrede, A. (2009). Pea protein concentrate substituting fish meal or soybean meal in diets for Atlantic salmon (Salmo salar)—Effect on growth performance, nutrient digestibility, carcass composition, gut health, and physical feed quality. Aquaculture, 288(3-4), 305-311. doi:10.1016/j.aquaculture.2008.12.012

Schmidt, V., Amaral-Zettler, L., Davidson, J., Summerfelt, S., & Good, C. (2016). Influence of Fishmeal-Free Diets on Microbial Communities in Atlantic Salmon (Salmo salar) Recirculation Aquaculture Systems. Appl Environ Microbiol, 82(15), 4470-4481. doi:10.1128/AEM.00902-16