WHAT SIZE TO HARVEST RAINBOW TROUT AND STEELHEAD IN RECIRCULATING AQUACULTURE SYSTEMS?

Transcription

1 WHAT SIZE TO HARVEST RAINBOW TROUT AND STEELHEAD IN RECIRCULATING AQUACULTURE SYSTEMS? BETH CLEVELAND,PHD, NCCCWA, KEARNEYSVILLE, WV STEVEN SUMMERFELT,PHD, TCFFI, SHEPHERDSTOWN, WV

2 RAINBOW TROUT (ONCORHYNCHUS MYKISS) MARKETS pigmented feeds 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

3 TWO MARKET TYPES: RAINBOW TROUT Rainbow Trout Size range: g, lbs Butterfly fillet Niche market sold mostly to restaurants Clearsprings.com 21food.com

4 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

5 ATLANTIC SALMON VERSUS TROUT Trout/Steelhead Atlantic Salmon Body Weight (g) Days Post Hatch 17 mon 21.5 mon

6 INCREASED GROWTH IN RAS Weight (g) NCCCWA TCFFI NCWMAC Casta Line RAS raceways Days post hatch RAS: 3 kg in 17 months!

7 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

8 AGE: GROWTH RATE AND THERMAL GROWTH COEFFICIENT 4 Body Weight 3.5 Body weight (kg) TGC TGC Body Weight Thermal Growth Cooefficient Days Post Hatch

9 AGE: GROWTH AND FEED CONVERSION Body Weight (kg) Body Weight FCR FCR Body Weight Feed Conversion Ratio (fed/gain) Days Post hatch

10 BASIS FOR INCREASED FCR Modified from Bailey, 2003

11 HOW RESEARCH CAN CONTRIBUTE Increase dietary energy/nutrient density Optimal pellet size Correct feeding regime Feed palatability

12 HOW RESEARCH CAN CONTRIBUTE Appropriate aquafeed ingredients Determine digestibility

13 HOW RESEARCH CAN CONTRIBUTE Optimal protein, fat, and carbohydrate ratio

14 HOW RESEARCH CAN CONTRIBUTE Optimize swim speed High oxygen Reduce stress Optimal temperature Maintain biosecurity

15 AGE: GROWTH AND HEAD-ON GUTTED YIELD Body Weight (kg) Body Weight HOG Yield HOG Yield Body Weight Head-On-Gutted Yield (%) Days Post Hatch

16 AGE: GROWTH AND BUTTERFLY FILLET YIELD Body Weight (kg) 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 Days Post Hatch Butterfly Fillet Yield (%)

17 CONSIDERATIONS FOR GROWTH AND FILLET YIELD Body Body Weight Weight (kg) (kg) Body Weight Skin-on Fillet Yield Fillet Yield oz x kg 2 x fillets 2 fillets Body Weight oz kg x 2 x 2 fillets fillets Skin-on Skin-on Fillet Fillet Yield Yield (%) (%) oz kg x 2 fillets Days Post Hatch Trimmed of belly flap and dorsal tissue

18 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% tons product 538 tons product 574 tons product $4.60/pound $ /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

19 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

20 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

21 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

22 FEED INTAKE: GROWTH AND FCR Live weight (g/fish) % 40% 60% 80% 100% a b c d e SGR: % per day SPG: % per day Feed Conversion Ratio Feed Conversion Ratio Week % 40% 60% 80% 100% % of satiation Cleveland and Burr, 2011

23 ECONOMIC BENEFITS OF FEED RESTRICTION 3 kg satiation moderate restriction Body weight >4% less feed Saves $50, per pound stock Fixed Time in tank harvest

24 NICHE MARKETS VALUE QUALITY Body Weight (kg) Body Weight (kg) Body Weight Fillet Fat Body Weight Shear Force Days Post Hatch Days Post Hatch Crude Fat (%) Shear Force Fillet fat concentration increases with age/size Fillets are firmer in older/larger fish

25 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 *

26 OBESITY AND HEART DISEASE IN THE US Coromega.com

27 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

28 PLOIDY-SPECIFIC GROWTH Sexually Mature 2N Poor fillet quality Poor FCR Slow growth month termination Sterile 3N Excellent fillet quality Continued growth Better FCR

29 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

30 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

31 QUESTIONS?

32 AHA recommends 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