Salmonids (primarily Atlantic salmon and rainbow trout) are the most cultured family of carnivorous fishes in the world, with 2004 production values of approximately two million metric tonnes (mmt) valued at US $6.5 billion (FAO 2006). The salmonid industry accounts for approximately 3% of total global aquacultural production, but its value is nearly 10% of total global aquacultural value (FAO 2006). Over the past ten years, the industry has more than doubled production output. Norway and Chile are the two primary producing countries, accounting for approximately 60% of global salmonid production (FAO 2006).

Commercial feed formulations for salmonids currently incorporate 30 to 45% fish meal (New and Wijkstroem 2002). Global fish meal production typically ranges between 6-7 mmt annually (FAO 2006). The salmonid industry is utilizing about one third of the total amount of fish meal used in aquaculture feeds (Hardy 2002). However, recent declines in the harvest of fishes utilized to produce fish meal (primarily in Peru) lead to an historic high of $1,600 per metric tonne of fish meal in the summer of 2006 (Hardy 2006). As fish meal prices climb, production costs for salmonid farmers increase as well (New and Wijkstroem 2002). Additionally, as fish farmers increase production, the economic return per unit of production decreases. For Atlantic salmon, the return per unit has decreased by 20-40% since 1986-1987 (FAO 2006). If the salmonid industry is going to continue to grow, alternative proteins will need to be incorporated into their feed formulations.

As the salmonid industry incorporates changes to their feed formulations, they need to assure that these changes have a minimal impact on fillet quality. Salmonid fillets are an excellent source of high quality protein. In addition, they contain high amounts of the n- 3 fatty acids eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. Farmed salmonids contain slightly higher levels of EPA and DHA than wild harvested salmonids, with farmed rainbow trout containing 1.15 g EPA and DHA per 100 g serving, compared to 0.99 g EPA and DHA per 100 g serving of wild caught rainbow trout. Farmed Atlantic salmon contain 2.15 g EPA and DHA per 100 g serving, compared to 1.80 g EPA and DHA per 100 g serving of wild caught Atlantic salmon (all values are cooked edible portion) (USDA/ARS 2006). The Food and Drug Administration (FDA) and American Heart Association (AHA) recommend two meals (one meal is 170.1-226.8 g) of fish per week, especially fatty species such as salmonids, to maintain a healthy lifestyle. In 2004, the FDA allowed a qualified health claim for reduced risk of coronary heart disease on conventional foods that contain EPA and DHA (FDA 2004). As the salmonid feed industry transitions to alternative protein and lipid sources, EPA and DHA levels in the diet and fillet will need to be considered.

Soybean meal (SBM) is an alternative protein ingredient currently of great interest to the aquaculture industry. In 2005, global production of soybean seeds was estimated at 218 mmt, but more importantly, global production of SBM was estimated to be 145 mmt, more than 20 times greater than the average global production of fish meal (USDA 2006). SBM prices can vary, but typically cost around US $200 per metric tonne (www.aquafeed.com). Dehulled SBM contains approximately 48% crude protein, one of the highest protein contents of all plant-based protein ingredients (NRC 1993). When used as a primary protein source, the essential amino acid profile of SBM, with the exception of methionine, is adequate to meet the known requirements of salmonids (NRC 1993).

Despite the global availability and nutritional characteristics of SBM, it has not been incorporated into salmonid diets at high inclusion rates. SBM is typically incorporated at 10-30% of the diet depending on species and feed manufacturer (Hardy 2002; Pillay and Kutty 2005). The relatively high concentration of carbohydrates and presence of antinutritional factors (ANF) are believed to be the primary factors limiting the amount of SBM used in salmonid feeds (Francis et al. 2001; Hardy 2002). Lectins, oligosaccharides, saponins and trypsin inhibitors are all present in SBM and have the ability to act as ANF when fed to fish. Soy isoflavones (also called phytoestrogens) may also exert negative effects when fed to fish by exerting estrogenic effects; however, isoflavones may also have a beneficial effect by acting as an antioxidant. Researchers have attempted to identify the specific components of SBM that are limiting its use in salmonid diets; however, most of this research evaluated SBM that had been subjected to various extraction techniques that removed several potential ANF instead of evaluating purified ANF derived from SBM (Francis et al. 2001). Consequently, the specific antinutritive compounds present in SBM that are exerting negative effects on salmonids have not been identified

In 2002, the United Soybean Board (USB) and the Indiana, Illinois and Ohio State Boards funded the Soy-in-Aquaculture (SIA) Managed Aquaculture Program. SIA was established to overcome the barriers limiting the amount of soy ingredients in aquaculture feeds. The initial SIA initiative contained two separate but related programs. The goal of the first component focused on increasing the amount of soy inclusion in feeds used by well-established, intensive aquaculture industries that were underutilizing soy in their feed formulations. Specific objectives were to systematically evaluate specific ANF and determine which ones were causing problems when fed to salmonids. This research was conducted at seven institutions, led by Purdue University (West Lafayette, IN, USA). The second program was international marketing led by the American Soybean Association/United States Soybean Export Council. The primary objective of that program was to increase usage of soy-based formulations by fish farmers in Southeast Asia and India. The remainder of this document will focus on the research portion of the SIA initiative.

The United Soybean Board’s Soy-in-Aquaculture(SM) Managed Research Program (SIA) and Archer Daniels Midland Company (ADM), announce a collaborative effort to establish a new soybean meal (SBM) nutrient database designed to help feed formulators use SBM in diets fed to aquatic animals. This collaborative effort marks the first full nutrient and anti-nutritional factor (ANF) characterization of SBM in aquatic animal diets. This characterization is important considering the fact that ANF levels in SBM vary significantly depending on various factors such as cultivar.

Prepared feeds for fish and shrimp are perishable products. They are also more or less fragile, depending on the type of feed. Feed processors attempt to formulate and manufacture aquaculture feeds to extend their shelf life and improve durability. However, the degree to which aquaculturists can reduce wasted feed and realize its full purchase value is ultimately dependent on how well the basic principles of feed storage and handling are understood and applied. Feed most often represents the greatest percentage of the total cost of raising fish and shrimp, and substantial amounts can potentially be wasted through spoilage and breakage. Even so, practical information about proper storage and handling of the most common types of feed is difficult to find, and usually only addressed in the literature in a general sense. Specific storage conditions and handling procedures are usually left to assumption. This article is intended to provide some detailed discussion, and information references where possible, on the most common causes of degradation and waste of aquaculture feed on the farm. It is impractical to address every conceivable storage and handling situation that may occur with each type of feed. However, guidelines presented here, along with some practical recommendations, should help in those instances where judgements or compromises are required.

Aquaculture has been the fastest growing agricultural sector for more than a decade and has become a significant contributor to global fisheries production. In 1996 aquaculture supplied approximately 73% of freshwater fish, 57% of mollusc, 43% of diadromous fish, and 17% of crustacean production worldwide. Projected population growth and static landings of capture fisheries indicate a need for aquaculture production to double by 2025 from its 1996 output of approximately 26 mmt. Industry use of feed-based production technologies is anticipated to rapidly increase demand for manufactured aquafeeds. Production of manufactured aquafeeds grew in excess of 30% annually in recent years. Growth in manufactured aquafeeds has been particularly strong in China, where aquafeeds are forecast to increase to 20% of market share of 100 mmt of premixed animal feed production by 2005. It is expected that strong demand for feed resources by the aquaculture industries of Asia, and particularly China, will significantly impact future world commodity markets and feed prices. Soybean products have become the focus of protein substitution in aquafeeds for every fed aquaculture species. Soybeans have the best amino acid profile of all protein-rich plant feedstuffs for fish. Soybean production can be structured to meet demand, and soybean meal is considerably less expensive and more consistent in quality than traditionally used marine animal meals. Research has demonstrated that soybean products can supply a major portion of the feed protein for nearly every fed aquaculture species around the world. Inclusion rates of up to 50% in aquafeeds for freshwater fish are projected to stimulate a demand for more than 6 mmt of soybean meal in China alone by 2005. The use of soy products in aquaculture is projected to increase significantly. Aquaculture will benefit from genetic improvements in soybeans and advances in feed processing and related technologies. High lysine, methionine and phytase soybean varieties currently under research will allow greater inclusion levels of soybean meal in aquafeeds. Processing advances in the removal of anti-nutritional factors will improve soybean utilization by aqua species. Research on attractant additives and synthetic flavorings will broaden opportunities for soybean product use in aquafeeds. Collectively these advances will result in greater demand for soybean products in all sectors of the aquaculture industry.

Shrimp aquaculture presently produces approximately one million metric tons of shrimp annually. While some 20 species are cultured in various parts of the world, the majority of production is based on eight species (Table1). For the eastern hemisphere, the fast growing giant tiger shrimp Penaeus monodon is the most important, while in the western hemisphere, the white shrimp Litopenaeus vannamei is the leading production species.

Shrimp have a complicated life cycle (Figure 1). Eggs from the female are broadcast into the marine environment. Hatching from the egg, the larvae pass through three distinct stages, nauplius, zoea and mysis, before assuming the distinctive adult morphology as post-larval or juvenile shrimp. The distinction between post-larva and juvenile is slight. Generally, the term post-larva is used for the first
month and juvenile thereafter.

Depending on one’s focus, shrimp aquaculture either started as trapping and holding of wild seed (Ling et al., 1977), or with the development of modern production techniques arising out of the research of the Japanese scientist Motosaku Fujinaga (Fast,1992). The “trap and hold” approach requires little effort on the part of the farmer, but yields are low and unpredictable. Traditionally with this type of
approach, the shrimp feed and grow on available pond organisms. In some cases where additional seed is sourced from the wild, supplementary feed may be added to the pond. Availability of seed is often the limiting factor for shrimp farmers using the “trap and hold” approach.

This bottleneck was partially bypassed by Fujinaga’s development of methods allowing captive reproduction of shrimp, starting with gravid females obtained from the wild, and completion of the larval cycle in hatcheries.

World aquaculture production is dominated by omnivorous fish species that live in freshwater, including various carp and catfish species. Soybean meal is a prominent ingredient used in prepared diets for these species, often constituting 50 to 60% of the total formulation. Such levels of incorporation are possible due to adequate palatability of soybean meal and its excellent nutritional value for these species, including high levels of crude protein, complementary amino acid profile and relatively high nutrient digestibility. For many omnivorous freshwater species cultured throughout the world, soybean meal has largely replaced more costly protein feedstuffs in diet formulations, such as fish meal, while maintaining optimal fish production. As a result, the cost of fish production has been reduced substantially. While aquacultural production continues to expand worldwide to meet the growing demand for seafood, the use of soybean products will play an even more important role in providing high-quality protein for various fish species.

Atlantic salmon, Pacific salmon and rainbow trout, collectively known as salmonids, are the most farmed carnivorous fish species in the world, mainly because they are prized food fish and relatively easy to culture. Salmon and trout can survive in a variety of environmental conditions, such as water temperatures from 0oC to as high as 28oC for some trout strains. They spawn successfully in water temperatures from 2oC to 15oC, and grow at temperatures from 6oC to 25oC. Depending upon their diet, salmon and trout can have pigmented (red) or non-pigmented (white) flesh. Salmon and trout are sometimes thought of as freshwater fish and other times as marine fish, but they are very adaptable to a variety of saline conditions.

The United Soybean Board’s Soy-in-Aquaculture(SM) Managed Research Program (SIA) and Archer Daniels Midland Company (ADM), announce a collaborative effort to establish a new soybean meal (SBM) nutrient database designed to help feed formulators use SBM in diets fed to aquatic animals. This collaborative effort marks the first full nutrient and anti-nutritional factor (ANF) characterization of SBM in aquatic animal diets. This characterization is important considering the fact that ANF levels in SBM vary significantly depending on various factors such as cultivar.

The results from the trials performed during 2007 for seabass indicated that the species is more sensitive to fishmeal/fishoil replacement than Gilthead seabream. In the treatments where FM was providing 35% of the protein, daily growth rate and food conversion were negatively affected compared to a control diet containing 65% FM protein. It was concluded that 40% FM protein was the main focus for the formulations of the 2008 program.

As marine ingredient levels are reduced in aquafeed, supplementation with low levels of taurine may be required to optimize production. Taurine may not only improve growth and performance, but also is required to reduce nutritional diseases such as green liver disease and low hematocrit levels in some fish. Taurine is authorized for fish feed in all species in the European Union and China, but not the United States.

Designing diets that are primarily soybean meal (SBM) instead of fishmeal will improve the overall sustainability of the aquaculture industry. A diet must provide good growth to the animal to which it is fed, but it should also neutrally or positively impact the ability of the animal to survive disease outbreak. Thus, a soybean-based diet for summer flounder that optimizes both growth and survival during bacterial challenge, would lead to enhanced profitability and sustainability of summer flounder aquaculture. It is well known that excess SBM in diets for fish can lead to intestinal pathologies like enteritis. However, in our previous work, we have demonstrated that SBM actually appears to stimulate the immune system of summer flounder, whereas soy protein concentrate (SPC) does not do so. Thus, it appears that something that is extracted from SBM to produce SPC (the fraction that is commonly referred to as soy molasses) contains one or more compounds that stimulate the immune system in these fish. We have funding from Rhode Island Sea Grant to identify the fractions of soy molasses that stimulate immune function, but it does not include sufficient funding to examine histopathology of the liver and pancreas or the blood chemistry for certain enzymes. USB funding is enabling us to do that work as part of the Sea Grant project. Although this work is directed toward the summer flounder industry, identification of soy molasses components that stimulate fish immune systems could be broadly applicable to other fish species in aquaculture as well. The concept is to use SPC as the main soy component of fish diets as the protein source, but then to add just the right amount of the appropriate soy molasses factor to boost the immune system as well.

Global demand for healthful seafood is growing at unprecedented rates due to…

U.S. soybeans provide a nutritious, safe and plentiful supply of protein for aquaculture feed. Soybeans can help global aquaculture scale up to meet increasing demand for healthful seafood, without depleting limited sources of wild-caught fishmeal and fish oil used in aquaculture feed…