International Journal of Marine Science, 2017, Vol.7, No.15, 130-140
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The global share of fish production used for direct human consumption was significantly expanded during the
latest decades. It is estimated at up to 67% in the 1960s to 87% or higher than 146 million tons in 2014. The left
over 21 million tons was ordained for non human consumption products. Of which 76% was reduced to fishmeal
and fish oil in 2014. The left over is used for a diversity of uses such as crude material for direct farmed fish
feeding. The usage of byproducts is becoming an essential industry. There is an increasingly emergent center of
attention on their usage in a safe, controlled, and hygienic way, thereby also reducing waste (FAO, 2016). Fish oil
and fishmeal are the major digestible and nutritious inputs for cultured fish feeds. Fishmeal and fish oil required in
feeds ingredients has shown a clear downward trend to offset their high prices, as feed demand increases, with
their being more selectively utilized as strategic components at minor concentrations and for only definite stages
of production, mainly hatchery, brood stock and finishing diets (FAO, 2016).
2.3 Climate change impacts on fishmeal production
Since 2005 production of fishmeal has declined gradually with the yearly oscillations affected by El Nino
phenomenon. While, in general the production requirements have sustained to rise, pushing prices to unexpected
historic highs during 2014. Prices then decreased until 2015 when high prospects for a strong El Nino started to
push up prices again. Due to this continuous demand of fishmeal, higher prices are anticipated to remain in the
long term. Total production was higher in 2015 compared to 2014, but Chile produced less. Peru and Chile, the
main exporters, registered the lowest export volumes in the past six years in 2015. China remai ned the chief
importer of fishmeal with 2015 import volumes equal to that in 2014 (FAO, 2016).
Aquaculture reliance on fish meal and fish oil becomes an important issue under most climate change scenarios
(De Silva and Soto, 2009). Because capture fisheries are an important protein and lipids sources for aquaculture,
changes in fisheries due to global climate change will impact aquaculture sector (Griffis and Howard, 2013).
In the North Atlantic, biological productivity is predicted to decrease by 50 percent while worldwide ocean
productivity is predicted to being decreased by 20 percent due to climate change impacts (Schmittner, 2005). This
would in turn greatly impact the availability of the small pelagic for fishmeal and oil production. The predicted
changes in ocean circulation pattern might also have a negative influence on the reliability of small pelagic stocks
that being utilized for fishmeal production. These changes in the fisheries productivity that cater to the fishmeal
and fish oil industry, and particularly considered as the main fisheries on which production of fish oil and fishmeal
is based, could limit the availability of raw materials (Griffis and Howard, 2013).
2.4 Potentials for fishmeal replacements in aquafeeds
Several studies on the different types of protein sources that have the ability of partially and/or totally replacing
fishmeal in aquaculture feeds without affecting performance of growth rates of fish are being extensively studied
(Tacon, 2004). Technology may lower the risks of higher prices and overfishing. It can provide substitutes to the
use of captured fish derived inputs. Fishmeal and fish oil substitution in aquafeeds with nutritionally equivalent
feedstuffs will diminish the reliance of different kinds of aquaculture on wild stocks. This substitution may also
minimize pressure on prices of feed inputs that resulting from capture fisheries.
Recently, inclusion rates of fishmeal in aquaculture feeds have been declined. Promising results may be obtained
by substituting protein rich oilseed and grain byproduct meals for fishmeal in carnivorous finfish and marine
shrimp diets. These vegetable based substitutes comprise wheat gluten, soybean, rapeseed and corn gluten. Lupin
and pea meals can be included. Other prospects for replacement may comprise terrestrial animal byproduct meals
like meat and bone meal. On the other hand, these replacements may raise awareness about the perceived risks for
the spread of different types of diseases (Delgado et al., 2003).
2.5 Plant by-products meals as alternatives protein source of fishmeal
The effectiveness of different types of alternatives protein sources as a partial or complete fishmeal substitution
has been previously studied by many authors in fish diets, e.g. sunflower meal (Merida et al., 2011; Sultan et al.,
2015), soyabean (Wu et al., 2016; Zhao et al., 2017; Wan et al., 2017; Yu et al., 2016), linseed meal (El-Saidy and
