6 Safe and Nutritious Aquaculture Produce
207
sufficient amounts of the lipid soluble vitamins A and D to support fish growth and
product quality, even at elevated levels that have been of concern for fish bone health
(Graff et al. 2002; Ørnsrud et al. 2002). Both FM (Table 6.3) and FO contain
considerable amounts of these vitamins, so there should be no risks for vitamin
deficiencies by use of vegetable feed substitutes. However, the benefits of vitamin
rich seafood would be reduced, since vitamin supplementations to gain similar feed
levels would not currently be supported by EC legislation (EC directive 1970).
6.8.3 Concerns on B-vitamins in Feed and Seafood
For water soluble B-vitamins, storage capacities in farmed fish are normally limited
and the muscle tissue will easily reach saturation level at moderate feed intake
levels. The possibility to manipulate the product through dietary means is therefore
limited. However, several fold variations in B vitamins in fish fillets may be seen
between species and relative to fillet muscle type (red or white muscle) and lipid
content, as well as relative to environmental factors, sexual maturation and annual
cycle (Brækkan 1959; Sandnes et al. 1998; Waagbø unpublished data). As a
traditional major protein raw material, FM supplies many of these vitamins in
adequate amounts and in readily available forms providing essential requirements
for growth and muscle saturation, including biotin (Mæland et al. 1998), vitamin
B12 (Mæland A, Sandnes, K and Waagbø R, unpublished data), panthotenic acid
(Sandnes et al. 1998) and riboflavin (Brønstad et al. 2002). Table 6.3 illustrates
differences in gross vitamin content in FM and soybean meal, the latter representing an important candidate among FM substitutes. Besides observed differences in
content, vitamins from plant raw materials may occur in other chemical forms
(pyridoxine, riboflavin, niacin, folic acid, vitamin B12) or together with antinutrients that results in lower bioavailabilities than vitamins from animal derived
raw materials (Machlin 1991). Even though this information is derived from
feeding studies or in vitro experiments in humans and terrestrial animals, this may
also be true for carnivorous fish species. Thus, care should be taken to fulfill the
optimal supply of these vitamins in aquafeeds containing FM substitutes through
micronutrient supplementation or by using selected vitamin-rich raw materials.
6.8.4 Antioxidant Vitamins and Pigments
The success of micronutrient tailoring of farmed fish fillet depends on the ability of
the fish species to handle the dietary intakes, through absorption, retention, metabolism and excretion. The concentrations of the antioxidant vitamins E and C in the
fish fillet are important for ensuring the oxidative storage stability of the highly
susceptible HUFAs as well as vitamins available to fish consumers (Hamre et al.
1998; Ng et al. 2004b; Waagbø et al. 1993; Yildiz et al. 2006). In a multivariate
207
sufficient amounts of the lipid soluble vitamins A and D to support fish growth and
product quality, even at elevated levels that have been of concern for fish bone health
(Graff et al. 2002; Ørnsrud et al. 2002). Both FM (Table 6.3) and FO contain
considerable amounts of these vitamins, so there should be no risks for vitamin
deficiencies by use of vegetable feed substitutes. However, the benefits of vitamin
rich seafood would be reduced, since vitamin supplementations to gain similar feed
levels would not currently be supported by EC legislation (EC directive 1970).
6.8.3 Concerns on B-vitamins in Feed and Seafood
For water soluble B-vitamins, storage capacities in farmed fish are normally limited
and the muscle tissue will easily reach saturation level at moderate feed intake
levels. The possibility to manipulate the product through dietary means is therefore
limited. However, several fold variations in B vitamins in fish fillets may be seen
between species and relative to fillet muscle type (red or white muscle) and lipid
content, as well as relative to environmental factors, sexual maturation and annual
cycle (Brækkan 1959; Sandnes et al. 1998; Waagbø unpublished data). As a
traditional major protein raw material, FM supplies many of these vitamins in
adequate amounts and in readily available forms providing essential requirements
for growth and muscle saturation, including biotin (Mæland et al. 1998), vitamin
B12 (Mæland A, Sandnes, K and Waagbø R, unpublished data), panthotenic acid
(Sandnes et al. 1998) and riboflavin (Brønstad et al. 2002). Table 6.3 illustrates
differences in gross vitamin content in FM and soybean meal, the latter representing an important candidate among FM substitutes. Besides observed differences in
content, vitamins from plant raw materials may occur in other chemical forms
(pyridoxine, riboflavin, niacin, folic acid, vitamin B12) or together with antinutrients that results in lower bioavailabilities than vitamins from animal derived
raw materials (Machlin 1991). Even though this information is derived from
feeding studies or in vitro experiments in humans and terrestrial animals, this may
also be true for carnivorous fish species. Thus, care should be taken to fulfill the
optimal supply of these vitamins in aquafeeds containing FM substitutes through
micronutrient supplementation or by using selected vitamin-rich raw materials.
6.8.4 Antioxidant Vitamins and Pigments
The success of micronutrient tailoring of farmed fish fillet depends on the ability of
the fish species to handle the dietary intakes, through absorption, retention, metabolism and excretion. The concentrations of the antioxidant vitamins E and C in the
fish fillet are important for ensuring the oxidative storage stability of the highly
susceptible HUFAs as well as vitamins available to fish consumers (Hamre et al.
1998; Ng et al. 2004b; Waagbø et al. 1993; Yildiz et al. 2006). In a multivariate