WHAT SIZE TO HARVEST RAINBOW TROUT AND STEELHEAD IN RECIRCULATING AQUACULTURE SYSTEMS? BETH CLEVELAND,PHD, NCCCWA, KEARNEYSVILLE, WV STEVEN SUMMERFELT,PHD, TCFFI, SHEPHERDSTOWN, WV
RAINBOW TROUT (ONCORHYNCHUS MYKISS) MARKETS pigmented feeds 400-500 g ~1 pound RAS or raceways ruby red trout rainbow trout pigmented feeds 1 3 kg ~2-6 pounds RAS or net pens steelhead 21food.com Clearsprings.com divinefishandmeat.com
TWO MARKET TYPES: RAINBOW TROUT Rainbow Trout Size range: 400-500 g, 0.5-1.0 lbs Butterfly fillet Niche market sold mostly to restaurants Clearsprings.com 21food.com
TWO MARKET TYPES: STEELHEAD Steelhead Size range: 1-3 kg, 2-6 lb Skin-on, pigmented fillets Follows the salmon commodity market Divinefishandmeat.com Bell Farms
ATLANTIC SALMON VERSUS TROUT 4000.00 3500.00 3000.00 Trout/Steelhead Atlantic Salmon Body Weight (g) 2500.00 2000.00 1500.00 1000.00 500.00 0.00 0 100 200 300 400 500 600 700 Days Post Hatch 17 mon 21.5 mon
INCREASED GROWTH IN RAS Weight (g) 4000 3500 3000 2500 2000 1500 NCCCWA TCFFI NCWMAC Casta Line RAS 1000 500 raceways 0 150 200 250 300 350 400 450 500 550 Days post hatch RAS: 3 kg in 17 months!
DIFFERENCES IN PRODUCTION EFFICIENCY WITH AGE It s not as simple as scaling up production Changes in Growth Rate Reductions in FCR with age Changes in product yield Product quality
AGE: GROWTH RATE AND THERMAL GROWTH COEFFICIENT 4 Body Weight 3.5 Body weight (kg) 3.5 3 2.5 2 1.5 1 0.5 TGC TGC Body Weight 3.0 2.5 2.0 1.5 1.0 0.5 Thermal Growth Cooefficient 0 0.0 150 200 250 300 350 400 450 500 550 Days Post Hatch
AGE: GROWTH AND FEED CONVERSION Body Weight (kg) 3.0 2.5 2.0 1.5 1.0 0.5 Body Weight FCR FCR Body Weight 1.3 1.2 1.1 1.0 0.9 Feed Conversion Ratio (fed/gain) 0.0 0.8 150 200 250 300 350 400 450 500 550 Days Post hatch
BASIS FOR INCREASED FCR Modified from Bailey, 2003
HOW RESEARCH CAN CONTRIBUTE Increase dietary energy/nutrient density Optimal pellet size Correct feeding regime Feed palatability
HOW RESEARCH CAN CONTRIBUTE Appropriate aquafeed ingredients Determine digestibility
HOW RESEARCH CAN CONTRIBUTE Optimal protein, fat, and carbohydrate ratio
HOW RESEARCH CAN CONTRIBUTE Optimize swim speed High oxygen Reduce stress Optimal temperature Maintain biosecurity
AGE: GROWTH AND HEAD-ON GUTTED YIELD Body Weight (kg) 4 3.5 3 2.5 2 1.5 1 Body Weight HOG Yield HOG Yield Body Weight 90.5 90 89.5 89 88.5 88 87.5 87 86.5 Head-On-Gutted Yield (%) 0.5 86 0 85.5 150 200 250 300 350 400 450 500 550 Days Post Hatch
AGE: GROWTH AND BUTTERFLY FILLET YIELD Body Weight (kg) 4 3.5 3 2.5 2 1.5 1 0.5 Body Weight Fillet Yield 231 g (2 x 3.7 oz) 541 g (2 x 9 oz) Butterfly Yield 1022 g (2 x 18 oz) 1766 g (2 x 31 oz) Body Weight 0 68.5 150 200 250 300 350 400 450 500 550 600 Days Post Hatch 70.5 70 69.5 69 Butterfly Fillet Yield (%)
CONSIDERATIONS FOR GROWTH AND FILLET YIELD Body Body Weight Weight (kg) (kg) 44 3.5 33 2.5 22 1.5 11 Body Weight Skin-on Fillet Yield Fillet Yield 20.56 oz x kg 2 x fillets 2 fillets Body Weight 28 0.8 oz kg x 2 x 2 fillets fillets 58 58 57 57 56 56 55 55 54 54 53 53 Skin-on Skin-on Fillet Fillet Yield Yield (%) (%) 0.5 52 52 9 oz kg x 2 fillets 00 51 51 150 200 250 300 350 400 450 500 550 600 Days Post Hatch Trimmed of belly flap and dorsal tissue
HOW DO THESE RESPONSES AFFECT PRODUCTION EFFICIENCY? Rainbow Trout 0.5 kg/1 lb ~1000 ton yearly harvest butterfly yield 58-68% Steelhead 1 kg/2 lb 3 kg/6 lb ~1000 ton yearly harvest fillet yield 53.8% 57.4% 580-690 tons product 538 tons product 574 tons product $4.60/pound $6.20-7.00/lb $5.3 - $6.3 million $7.0 million $7.5 million feed costs - $1.3 million feed costs -$1.4 million -$1.6 million $4.0 - $5.0 million $5.6 million $5.8 million * Does not account for processing or infrastructure costs
BUT IT DEPENDS ON RAS PRODUCTION CAPACITY Rainbow Trout 500 g/1 lb Steelhead 1 kg/2 lb 2 kg/4 lb 3 kg/6 lb 260 days 334 days 425 days 491 days Rainbow Trout, 500 g/1 lb ~84 dph, 1.8 g Cohort 1 Cohort 2 Scenario #1 0-6 month grow-out 7-12 month grow-out 0-4 month grow-out 5-8 month grow-out 9-12 month grow-out Cohort 1 ~142 dph, 20 g Cohort 2 Cohort 3 Scenario #2 50% more production
BUT IT DEPENDS ON RAS PRODUCTION CAPACITY Rainbow Trout 500 g/1 lb Steelhead 1 kg/2 lb 2 kg/4 lb 3 kg/6 lb 260 days 334 days 425 days 491 days Steelhead, 1 kg/2 lb ~158 dph, 25g Cohort 1 Cohort 2 Scenario #1 0-6 month grow-out 7-12 month grow-out 0-4 month grow-out 5-8 month grow-out 9-12 month grow-out Cohort 1 ~216 dph, 200 g Cohort 2 Cohort 3 Scenario #2 50% more production
BUT IT DEPENDS ON RAS PRODUCTION CAPACITY Rainbow Trout 500 g/1 lb Steelhead 1 kg/2 lb 2 kg/4 lb 3 kg/6 lb 260 days 334 days 425 days 491 days Steelhead, 3 kg/6 lb Cohort 1 ~315 dph, 500 g Cohort 2 ~315 dph, 500 g Scenario #1 0-6 month grow-out 7-12 month grow-out 0-12 month grow-out Cohort 1 ~139 dph, 18 g Scenario #2 50% less production
FEED INTAKE: GROWTH AND FCR Live weight (g/fish) 350 300 250 200 150 100 20% 40% 60% 80% 100% a b c d e SGR: % per day 1.4 1.2 1.0 0.8 0.6 0.4 0.2 SPG: % per day Feed Conversion Ratio 2.0 1.8 1.6 1.4 1.2 1.0 Feed Conversion Ratio 0 2 4 6 8 10 12 Week 0.0 20% 40% 60% 80% 100% 0.8 75% of satiation Cleveland and Burr, 2011
ECONOMIC BENEFITS OF FEED RESTRICTION 3 kg satiation moderate restriction Body weight >4% less feed Saves $50,000 2.3 per pound stock Fixed Time in tank harvest
NICHE MARKETS VALUE QUALITY Body Weight (kg) Body Weight (kg) 4 3.5 3 2.5 2 1.5 1 0.5 0 6 150 250 350 450 550 4 3.5 3 2.5 2 1.5 1 0.5 0 Body Weight Fillet Fat Body Weight Shear Force Days Post Hatch 160 150 250 350 450 550 Days Post Hatch 14 13 12 11 10 9 8 7 510 460 410 360 310 260 210 Crude Fat (%) Shear Force Fillet fat concentration increases with age/size Fillets are firmer in older/larger fish
OMEGA-3 / N-3 FATTY ACIDS: METABOLISM AND HEALTH ALA Poorly converted to EPA and DHA * EPA Reduction of Platelet Reactivity Reduce Inflammation * DHA Brain Development Reduction of Arrhythmias Reduce Inflammation *
OBESITY AND HEART DISEASE IN THE US Coromega.com
LIPID DEPOSITION: EFFECTS OF DIET AND AGE You are what you eat! Fish are too. Dietary lipid profile Body lipid profile Lipid Distribution central ventral ventral central Weil et al., 2012
PLOIDY-SPECIFIC GROWTH Sexually Mature 2N Poor fillet quality Poor FCR Slow growth 18-20 month termination Sterile 3N Excellent fillet quality Continued growth Better FCR
CONCLUSION: LARGER FILLETS ARE MORE LUCRATIVE Reductions in FCR with age Offset by increased product yield and higher prices Changes in product yield Higher muscle mass in 1+ kg steelhead Product quality Market-dependent Light/delicate fillets versus salmon-like Production efficiency Invest in nursery tanks for multiple cohorts
ACKNOWLEDGEMENTS The Conservation Fund s Freshwater Institute Dr. Chris Good, John Davidson, Travis May, Curtis Crouse National Center for Cool and Cold Water Aquaculture Dr. Tim Leeds, Josh Kretzer, Lisa Radler, Kyle Jenkins Grand Forks Human Nutrition Research Center Dr. Matt Picklo, Dr. Susan Raatz West Virginia University Dr. Brett Kenney Pacific Aquaculture Craig Applewood
QUESTIONS?
AHA recommends 250-500 mg DHA/EPA per day ~2-3 kg rainbow trout/steelhead: 13 mg DHA/EPA per g fillet 8 oz fillet portion (~225 g) = 3000 mg DHA/EPA