Advancements in Nutrition and Feeding of Marine Advancements in Nutrition and Feeding of Marine Fish to Ensure Sustainable Seafood ProductionFish to Ensure Sustainable Seafood Production

Delbert M. Gatlin, III

Department of Wildlife and Fisheries Sciences and Faculty of Nutrition,

Texas A&M University System,College Station, Texas

0

20

40

60

80

100

120

140million metric tons

80 85 90 95 99

year

Total

Fisheries

Aquaculture

World Fisheries & Aquaculture Production

FAO, 2001

• Approximately 30% of all seafood is now produced via aquaculture

• Continued growth of aquaculture will be needed to satisfy demand for

seafood by the world’s ever increasing population

Benefits of AquacultureBenefits of AquacultureBenefits of AquacultureBenefits of Aquaculture

Production of aquatic organisms under controlled conditions allows for:

superior product quality and freshness

consistent supply

value/quality enhancement

efficient use of natural resources

Production of aquatic organisms under controlled conditions allows for:

superior product quality and freshness

consistent supply

value/quality enhancement

efficient use of natural resources

Perceived Limitations to Perceived Limitations to AquacultureAquaculture

Perceived Limitations to Perceived Limitations to AquacultureAquaculture

• Available land and freshwater resources

• Release of eutrophying nutrients into the water – degree of control is dictated by type of culture system

• Dependence of certain species on marine resources such as fish meal and fish oil

• Available land and freshwater resources

• Release of eutrophying nutrients into the water – degree of control is dictated by type of culture system

• Dependence of certain species on marine resources such as fish meal and fish oil

Phosphorus balance, 1990 trout feed

Feed2.2% P

Feces0.9% P

urine0.6% P

Retention by fish0.7%

Phosphorus balance, 2000 trout feed

Feed1.2% P

Feces0.3% P

urine0.2% P

Retention by fish0.7%

Nutritional Advancements to Reduce Phosphorus Excretion

Hardy (2004)

Nutritional Advancements to Reduce Nitrogen Excretion

Nitrogen balance, 2000 trout feed

Feed7.9% N

Gill excretion3.8% NFeces

0.8% N

urine0.1% N

3.2% retained

Nitrogen balance, 1990 trout feed

Feed7.4% N

Gill excretion3.7% NFeces

1.5% N

urine0.1% N

2.2% retained

Hardy (2004)

Fishmeal Use in AquafeedsFishmeal Use in AquafeedsFishmeal Use in AquafeedsFishmeal Use in Aquafeeds

• Year 2000 - Approximately 2 million metric tons (MMT) of fish meal were used in aquafeeds (~30% of global fishmeal production @ 6.5 MMT)

• Year 2010 - Approximately 4.3 MMT of fish meal are projected to be used in aquafeeds if aquaculture continues to grow at its current rate

• Currently about 70% of the fishmeal is used by salmon, trout and shrimp which constitute ~7% of global aquaculture production

• Year 2000 - Approximately 2 million metric tons (MMT) of fish meal were used in aquafeeds (~30% of global fishmeal production @ 6.5 MMT)

• Year 2010 - Approximately 4.3 MMT of fish meal are projected to be used in aquafeeds if aquaculture continues to grow at its current rate

• Currently about 70% of the fishmeal is used by salmon, trout and shrimp which constitute ~7% of global aquaculture production

Fishmeal Reduction in Fishmeal Reduction in AquafeedsAquafeeds

• A greater understanding of nutritional requirements of fish is allowing refinement of diet formulations including ingredient substitutions

• Significant advancements have been made in these areas over the past 10 years with intensified research

• Specific examples of advancements with Atlantic salmon, red drum and rainbow trout are provided

Alternatives to Fishmeal in Alternatives to Fishmeal in AquafeedsAquafeeds

• Various plant feedstuffs including: Oilseed meals such as soybean meal and

cottonseed meal

Protein concentrates from cereal grains such as corn gluten meal and wheat gluten

• Animal by-products rendered from processing plants including seafood processing wastes

• Single-cell proteins

VisionStimulate sustainable growth in the aquaculture

industry by providing necessary knowledge for optimal use of protein in fish feeds.

• Bacteria grown on methane as a carbon source from the North Sea Bacteria grown on methane as a carbon source from the North Sea

Methylococcus capsulatusMethylococcus capsulatusAlcaligenes acidovoransAlcaligenes acidovoransBacillus brevisBacillus brevisBacillus fermusBacillus fermus

• BioProtein contains:BioProtein contains:

93.5 % dry matter93.5 % dry matter64.9 % crude protein64.9 % crude protein 7.6 % fat7.6 % fat 5.8 % ash5.8 % ash10.3 % nucleic acids10.3 % nucleic acids20.9 MJ/Kg20.9 MJ/Kg

BioProteinBioProteinTMTM

Diet composition (g/ 100 g)Diet composition (g/ 100 g)

IngredientIngredient 0 0 5.7 5.7 11.4 11.4 22.8 22.8 45.5 45.5

BioProteinBioProtein 00 4.54.5 99 1818 3636

LT Fish MealLT Fish Meal 65.065.0 61.361.3 57.657.6 50.250.2 35.435.4

WheatWheat 14.114.1 13.213.2 12.312.3 10.510.5 6.86.8

Fish OilFish Oil 20.520.5 20.620.6 20.720.7 21.021.0 21.521.5

YY22OO33 0.010.01 0.010.01 0.010.01 0.010.01 0.010.01

Mineral MixMineral Mix 0.250.25 0.250.25 0.250.25 0.250.25 0.250.25

Vitamin MixVitamin Mix 0.100.10 0.100.10 0.100.10 0.100.10 0.100.10

Fish meal replacement (%)

0 0 5.7 5.7 11.4 11.4 22.8 22.8 45.545.5

Final wt (g)Final wt (g) 330330 327327 345345 364364 360360

SGRSGR 1.381.38bb 1.371.37bb 1.491.49abab 1.591.59aa 1.561.56aa

Gain:FeedGain:Feed 1.391.39bcbc 1.361.36cc 1.451.45abcabc 1.471.47abab 1.541.54aa

% Nitrogen % Nitrogen retentionretention

46.246.2bb 45.545.5bb 52.752.7aa 52.752.7aa 55.155.1aa

% Energy % Energy retentionretention

50.550.5bcbc 48.348.3cc 55.855.8abab 58.858.8aa 58.658.6aa

Results of 8-week Feeding Trial Results of 8-week Feeding Trial

Fish meal replacement (%)

Red Drum (Red Drum (Sciaenops ocellatusSciaenops ocellatus))

• Prominent fish in Gulf coast Prominent fish in Gulf coast states of the USstates of the US

• Popular recreational species Popular recreational species targeted for stock targeted for stock enhancement enhancement

• Also a seafood delicacy with Also a seafood delicacy with commercial aquacultural commercial aquacultural production occurring in the US production occurring in the US and expanding rapidly in Asia and expanding rapidly in Asia

Red Drum Commercial FisheryRed Drum Commercial Fishery

• Historically sustained harvest of ~1 million pounds in the Gulf coast states until early 1980s

• “Blackened redfish” craze heightened demand and jeopardized wild stocks

• State of Texas prohibited sale of wild red drum in 1981

Conservation & Restoration Conservation & Restoration EffortsEfforts

• Adaptive & Integrative Management Adaptive & Integrative Management

• Habitat Conservation & RestorationHabitat Conservation & Restoration

• Outreach & EducationOutreach & Education

• Stock Enhancement ProgramStock Enhancement Program– Annually ~30 million red drum Annually ~30 million red drum

fingerlings releasedfingerlings released(2003 production estimate(2003 production estimate))

“…optimizing the long-term utilization and sustaining fisheries populations at levels that are necessary to ensure replenishable stocks of commercially and recreationally important species.” – TPWD - Coastal Fisheries Management Strategy

Red DrumRed Drum NutritionNutrition

• Most of the critical nutrient requirements have Most of the critical nutrient requirements have been quantified for this species to allow refined been quantified for this species to allow refined commercial diet formulations commercial diet formulations

• This species requires relatively high levels of This species requires relatively high levels of dietary protein (~40%) as other marine carnivoresdietary protein (~40%) as other marine carnivores

• Diet formulations initially contained relatively high Diet formulations initially contained relatively high levels of fish meallevels of fish meal

• Efforts have been made to reduce dependence Efforts have been made to reduce dependence on fish meal by evaluating various alternatives on fish meal by evaluating various alternatives such as marine by-products and plant feedstuffssuch as marine by-products and plant feedstuffs

Marine By-Products Evaluated with Red Drum and Rainbow Trout in a Nat’l

Marine Aquaculture Initiative Project • Shrimp by-catch mealShrimp by-catch meal – assorted fish from Gulf – assorted fish from Gulf

shrimp trawlersshrimp trawlers

• Shrimp waste mealShrimp waste meal – processing waste from – processing waste from aquacultured shrimp aquacultured shrimp

• Pacific whiting Pacific whiting

• Pacific whiting with solubles Pacific whiting with solubles

• Red salmon head meal Red salmon head meal – – processing waste of red processing waste of red salmon from Alaskasalmon from Alaska

Results with Red Drum Results with Red Drum and Rainbow Troutand Rainbow Trout

• By-catch from shrimp trawls and red salmon meal By-catch from shrimp trawls and red salmon meal are nutritious replacements of fish mealare nutritious replacements of fish meal

• More limited substitution of menhaden fish meal More limited substitution of menhaden fish meal (< 50%) with other by-products will be possible (< 50%) with other by-products will be possible without reducing fish performancewithout reducing fish performance

• Utilization of shrimp-processing waste may be Utilization of shrimp-processing waste may be limited by excessive chitin limited by excessive chitin

• Digestibility coefficients of the various by-product Digestibility coefficients of the various by-product meals will allow substitution of other feedstuffs on meals will allow substitution of other feedstuffs on an available-nutrient basis an available-nutrient basis

• Palatability of plant feedstuffs may be limited for some Palatability of plant feedstuffs may be limited for some carnivorous species and digestibility of certain nutrients carnivorous species and digestibility of certain nutrients may be reducedmay be reduced

• Compared to fish meal, sulfur amino acids (methionine + Compared to fish meal, sulfur amino acids (methionine + cystine) and/or lysine may be limiting in plant feedstuffscystine) and/or lysine may be limiting in plant feedstuffs

• Amino acid supplementation may be required when Amino acid supplementation may be required when replacing fish meal replacing fish meal

Limitations of Plant FeedstuffsLimitations of Plant Feedstuffs

Menhaden Soybean DL- AlimetTM

fish meal meal methionine

Protein % 64 50

Methionine % 1.75 0.68

$/unit wt. 0.26 0.10

$/unit prot. 0.39 0.20

$/unit Met 14.5 14.5 2.0 1.26

Ingredient ComparisonsIngredient Comparisons

Weight GainWeight Gain

050

100150200250300350400450500

Per

cen

t o

f in

itia

l w

t.

Basal L-met DL-met MHA Met:Lys

Diet

Exp. 1p-value = 0.0001

B

A A A A

Practical Diet Formulations for Feeding Red Drum from Juvenile to Market Size (1.5 kg)

Ingredient Formulation (% as fed) A B1

Menhaden fishmeal 32.3 5.5Soybean meal (48% protein) 26.0 66.0Meat and bone meal 10.0Wheat 26.0 13.1Menhaden fish oil 5.0 5.2Mineral premix 0.1 3.0Vitamin premix 0.1 4.0Dicalcium phosphate 0.5 2.6 DL-methionine 0.8

1 McGoogan and Gatlin (1997)

ConclusionsConclusions• A greater understanding of nutritional needs of marine

species is allowing for refinement of diet formulations

• Various alternatives to fish meal and other marine ingredients have been identified and are effectively replacing fish meal

• Advancements in nutrition and feeding of fish have not only reduced production costs, but also may favorably influence compositional attributes and reduce nutrient excretion into the environment

• Further nutritional refinements and manipulations also hold promise to aid in improving immunity and disease resistance of cultured fish