The Aquaculture sector continues growing and making important contributions to world food supplies. However, it is required to focus on the good practices related to fish-feed use, manufacturing, and quality to ensure this expansion in a socially, economically, and environmentally sustainable manner. This article guides from a holistic approach to guarantee the long term sustainable development of the aquaculture sector.
Since the first FAO publication of technical guidelines for aquaculture development (FAO 1997), the FAO has published two feed-related guidelines, the first concerning good aquaculture feed manufacturing practice, and the second concerning the use of wild fish as feed.
In particular, controversy has arisen since the use of the term “fish-in fish-out” (FIFO) as a metric for the use of fishmeal and fish oil in compound aquafeeds, and the perceived long-term sustainability of the aquaculture sector dependent upon these wild fishery resources.
“In specific, concerning the methodology used for converting fishmeal and fish oil use back to live fish weight equivalents.”
Some studies have shown polemics in the FIFO values, as consequence, a series of derived ratios/ indexes have been developed; however, most if them are providing a good picture of the pressure on the wild resource while they are failing to fully cover the sustainability aspect.
To note, the FIFO ratio was never intended to be a precise measurement of how much wild fish is required to produce a given amount of farmed fish. It was to bring attention to the reliance of the aquaculture feed industry on wild capture fisheries.
Further with much of the aquaculture sector seeking to portray farmed seafood as a solution or alternative to wild capture fisheries, the FIFO ratio highlighted the specific dependence aquaculture has on wild capture fisheries.
“Additionally, some critics of the aquaculture sector have been primarily focused on wild fish dependency because of a marine conservation focus.”
The narrow focus of these critics fails to recognize that there are tradeoffs in environmental impact in the substitution of ingredients for wild fish, i.e. soy and deforestation/conversion, manufactured novel ingredients and energy consumption, etc.
So while useful as a guidepost and a magnitude snapshot of aquaculture’s reliance on wild fisheries, there is a broader lens by which the aquafeed sector should be viewed to account for these tradeoffs and other impacts on ingredient production and feed manufacturing.
Need for a more holistic “feed-in fishout” approach
It is clear that the FIFO metric, like other ratios/index, is not an indicator of sustainability per se unless it is linked with the sustainability or not of the specific fishery and/or processing waste targeted for fishmeal and fish oil production.
There is a need for a more holistic approach that considers other feed-related factors to ensure the longterm sustainable development of the aquaculture sector as the four levels of action are described below.
1ST Sustainability issues related to feed formulation and ingredient selection
It is required the need to prohibit the use of
i) non-sustainable marine feed ingredient sources, including meals, oils, and silages/hydrolysates derived from over exploited and/ or non-sustainable managed wild-caught marine fish, crustaceans, mollusks, and aquatic plant species,
ii) non sustainable and/or adulterated terrestrial feed ingredient sources, including meals derived from endangered and/ or protected wild animal species,
iii) non-approved terrestrial feed ingredient sources for perceived religious and/or food safety concerns, including feeds containing terrestrial animal by-product meals, genetically modified plant feed ingredients, and animal manures,
iv) the re-feeding of feed ingredients derived from the same species for biosecurity concerns,
v) nonapproved chemicals, medicaments & feed additives.
It is recommended the need to reduce the carbon footprint of aquafeeds through the reduced use of imported feed ingredient sources and the increased use and recycling of locally available agricultural and fishery resources derived from sustainably managed and operated agricultural and fishery operations, and also, limit the selection and use of potentially food-grade feed ingredient sources, including fisheries bycatch, small pelagic fish species, and food-grade cereal grains, starches, pulses, and oilseeds.
2nd Sustainability issues related to feed manufacture and feed quality
It is required the need to ensure:
i) that the feed manufacturing plant is run and operated following all national laws and local environmental/social standards, and according to standards, guidelines, and criteria concerning the manufacture of compound aquafeeds developed by FAO, the Global Partnership for Good Agricultural Practice (GLOBAL G.A.P.), the Global Aquaculture Alliance (GAA), and/or the Aquaculture Stewardship Council (ASC);
ii) oversight in feed ingredient supply chains to demonstrate to buyers and authorities that ingredients are not produced with forced or child labor;
iii) that feeds produced by the feed plant are formulated to meet the dietary nutrient requirements of the target species for optimum growth and health (NRC 2011), and for the intended farming system and stocking density (FAO 2001).
In addition, it is required for the feed plant to have a dedicated laboratory for feed quality control, including the use of both Near Infra Red and wet chemical analytical techniques for the routine analysis of feeds and feed ingredients, including proximate analysis, specific nutrient analysis (if so required), and screening for mycotoxins and possible adulterants/contaminants.
“And also, for transparency concerning feed ingredient use and the open declaration of all major feed ingredients and feed additives used on feed bags and/or labels (listed from highest to lowest), as well as key essential dietary nutrient levels.”
It is Encouraged the need to minimize the use of feed mill sweepings and processing wastes (includes floor sweepings and rejected processed feeds due to quality concerns) within finished feeds; also the need for the feed mill to establish a dedicated research and development (R&D) program and facility for the routine in-house testing of novel feed additives, feed ingredients, and feed formulations, including for determining the apparent nutrient digestibility of the feed ingredients used by the feed plant; and finally, the need for the feed mill to dedicate sufficient funds and resources (including personnel) for farm data collection and technical support to farmers concerning the storage and management (feeding) of their feeds, including training for both large-scale and small-scale farmers.
3rd Sustainability issues related to on-farm feed use and impacts
It is required the need for farmers:
i) to monitor and record feed consumption, fish/shrimp biomass, survival, and apparent biological and economic feed efficiency regularly,
ii) to store their feeds in under-protected, cool and well-ventilated conditions to maintain feed quality, and nutrient stability,
iii) non-top-dressing their feeds with non-approved feed ingredients and feed additives,
iv) to optimize feed intake and feed efficiency of the cultured species and water quality conditions, following internationally recognized good or best on-farm feed management practices,
v) monitor the environmental impact of their feeds by checking waste nutrients levels over the culture cycle, and by minimizing their potential negative environmental impacts through water-recirculation and/or effluent treatment/IMTA before discharge.
Encouraged farmers to establish a dedicated R&D program and facility on-farm for the in-house testing of different feeds and feeding regimes so as reduce feed costs and optimize their feeds and feeding systems; need to increase communication and information between farmers, feed manufacturers, policymakers, consumers, and researchers so as optimize onfarm feed use, farm management, profitability, and the long-term sustainability of the aquaculture sector.
4TH Sustainability issues related to fish quality and food safety
It is required the need to ensure that feeds used by farmers have no negative effect on the nutritional quality and safety of aquaculture products, and the need to monitor the nutritional composition, quality and safety of aquaculture products destined for direct human consumption, including whole fish/shrimp, gutted fish, shrimp tails, fish fillets, fish balls, fish sausages, fish burgers, nuggets, etc., depending upon the species and country of origin.
Encouraged the need to maximize the use of aquaculture derived trimmings and fish/shrimp off-cuts for direct human consumption whenever possible, including the production of lower-cost (in marketing terms) fast-food and/or ready-made meals for mass consumption and the need to encourage the nutritional enhancement and potential health attributes of aquaculture products through dietary fortification with limiting key essential nutrients; need to promote public awareness and understanding concerning the nutritional and health benefits of farmed aquatic food products and by so doing encouraging increased consumption of aquaculture products (Tacon et al. 2020); and need to promote public awareness and understanding concerning resource-use efficiency, nutrient retention efficiency, and environment/climate change impacts of different cultured fed-fish and shrimp species production compared to other terrestrial animal food production systems from feed to consumed product.
With the total global production of major fed-aquaculture species reaching a new high of 45.41 million tons in 2018 and compound feed consumption estimated at 52.74 million tons (Figure 1, Table 1), fed-species aquaculture production is expected to grow by 58.96 million tons by 2025 (Tacon 2020).
However, to achieve this growth the aquafeed industry has to grow at an average rate of 7.7% per year (Figure 2), including the supply of feed ingredient inputs.
However, in the case of fishmeal and fish oil, the aquafeed industry has successfully learned how to reduce its reliance upon these two limited natural commodities. For example, the average fishmeal and fish oil content of Norwegian salmon feeds have fallen over a 30 years from a high of 65% and 24% in 1990 to a low of 13% and 11% in 2019, respectively.
The decreased dependency of the aquafeed manufacturing sector in Norway upon fishmeal and fish oil has been due to the increased use of terrestrial vegetable and animal protein and lipid sources, and dietary supplementation with limiting essential amino acids, fatty acids, and trace minerals.
“Notwithstanding the dependency upon marine feed resources (and in particular fish oil), the salmonid aquaculture sector has received considerable negative media attention in several European and North/South American countries, primarily due to its perceived negative environmental impacts.”
In marked contrast, in the Asian region, where the bulk of aquaculture production is currently realized (91.76% of total global aquaculture production in 2018), aquaculture is viewed in a much more positive light, not only as a much-needed supplier and provider of high quality affordable aquatic food products but also in terms of employment opportunities, and increased income, health and well-being of rural inland, and coastal communities.
Aquaculture needs to be viewed holistically, and the social and economic impacts and benefits of the aquaculture sector also be considered in the overall assessment of the long-term sustainability of the sector for future generations.
Careful management of this sector is a key feature of a sustainable future.
In conclusion, a sustainable food system (SFS) is a food system that delivers food security and nutrition for all in such a way that the economic, social, and environmental bases to generate food supply and nutrition for future generations are not compromised, and that it is profitable throughout (economic sustainability), has broad-based benefits for society (social sustainability), and also has a positive or neutral impact on the natural environment (FAO 2014, 2018).
Moreover, given the complexity of food production systems (including aquaculture food production systems) it is clear that a more holistic and coordinated response is required to generate positive value along the three dimensions of economic impacts, social impacts, and environmental impacts, simultaneously (Figure 3; FAO 2018).
This is a summarized version developed by the editorial team of Aquaculture Magazine based on the review article titled “FUTURE FEEDS: SUGGESTED GUIDELINES FOR SUSTAINABLE DEVELOPMENT” developed by ALBERT G. J. TACON – Aquahana LLC, Kailua, Hawaii, USA; MARC METIAN – Principality of Monaco, International Atomic Energy Agency, Monaco; AARON A. MCNEVIN – World Wildlife Fund, Washington, DC, USA. The original article was published in REVIEWS IN FISHERIES SCIENCE & AQUACULTURE, in DECEMBER 2021. The full version can be accessed freely online through this link https://doi.org/10.1080/23308249.2020.1860474