Barramundi – the Next Big Global Marine Finfish

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Barramundi – the Next Big Global Marine Finfish Barramundi – the next big global marine finfish Dean Jerry Centre for Sustainable Tropical Fisheries and Aquaculture James Cook University Australia Presentation outline . Global changes in food commodity consumption . Barramundi as the gap filler . Biological attributes of barramundi . Broodstock management . Hatchery production . Challenges to farming . Potential in Brazil Changing populations with changing diets 27% Cereals 58% 28% Fruit and vegetables 18% Sugars and 30% alcohol Meat, fish 27% 6% and other 7% products Developing Developed Changing populations with changing diets 27% Cereals 58% 28% Fruit and vegetables 18% Sugars and 30% alcohol Meat, fish 27% 6% and other 7% products Developing Developed Changing populations with changing diets The portfolio gap The portfolio gap What is barramundi? Species: Lates calcarifer Snooks (Americas) Nile perch (Africa) Centropomus sp. Lates niloticus Distribution of barramundi/seabass Australia vs SEAsiaBarramundi vs Australia Australia Indonesia - KM Indonesia - SW SE Asia SE Vietnam Cambodia Philippines Catadromous and protandrous life-history Catadromous - live in fresh water but migrate to marine waters to breed Protandrous Hermaphodite – born males and change sex into females later in life Attractiveness for farming Euryhaline (wide salinity tolerance): Cultured in fresh, brackish or seawater Fast growth: 1 kg in 1 year Accept well artificial food: wean onto pellets early, specialised diets available Good Feed Conversion Ratio FCR = < 1.5 :1 (Kg feed : Kg fish) Hardy: up to 100 kg / m3, 50t/ha Food conversion efficiency Strong consumer preference Versatility of farming systems Freshwater/brackish ponds Sea Cages Intensive raceways RAS Production Statistics - Global Production Statistics - Australia Production Statistics - Australia Broodstock management . Require saltwater (28-35ppt) for final gonadal maturation . Tanks – 10 000 – 50 000L . Ponds – ½ ha . Net cages . Feeding (3x/wk): fish, squid, commercial broodstock feed, Vitamin E Broodstock management H O R M O N A L M Anesthetised fish A N I.D. checks: weight, sex, history… IP U 400 μm If broods ready: L ____ A Intramuscular TI Injection of LHRHa* O N F: 50-100 μg/Kg Eggs examined M: 25 μg/Kg Cannulation of broodstock via microscopy * LHRHa: Luteinising Hormone Releasing Hormone analogue Highly fecund species Hatchery management - Nutrition Standard marine finfish larviculture protocols • 30 to 150 larvae / L • ideal 29C & 30ppt DAYS AFTER HATCH (DAH) Fertilized eggs float 1 2 8 10 14 15 19 22 24 ALGAE (ex. Chlorella sp.) ROTIFER (Brachionus sp.) ARTEMIA NAUPLI HUFA ENRICHED ARTEMIA Egg collector ARTIFICIAL FEED 2 DAH 6 DAH 11 DAH 14 DAH Day 40 – ready to leave the hatchery 7,253,000 fingerlings out of a room 5 x 5 m2 Hatchery management - grading 16 DAH Grade weights 27 DAH 0.25 0.20 0.15 0.10 0.05 Mean Mean weight (g) Continuous grading is 0.00 required after 16-20 DAH to Small Medium Large Extra large. improve survival and avoid even greater size differences Hatchery management - grading Hatchery management - grading Nursery Culture Growout • Stock 100 mm animals (50g) • Ponds 5,000-20,000 fish/ha • Cages 10-15 fish/m3 • Survival >85% • Harvest – Plate size (600-1000g) – Fillet size (2-3kg) Growout kg/m3 120 100 80 60 40 20 0 Pond Seacage RAS kg/m3 Growout (optimal temp) Challenges to Farming - Sex change • Broodstock management • Infrastructure • Selective breeding Diseases of barramundi Hatchery phase Nursery phase Pre growout Growout Ponds/tank tanks Small cages Ponds/cages etc 0 Days of culture (DOC) 40 DOC 80 DOC 140 DOC 400 DOC 0 g 2 g 20 g 150 g 1.5 kg VNN Big belly Iridovirus Benedenia parasites Streptococcus iniae Scale drop disease Challenges to Farming - Selection • High heritability growth, low GxE • Mass spawning, sex change, infrastructure resourcing challenges • Selective breeding programs – Singapore – Indonesia – Australia Challenges to Farming – Flavour tainting Geosmin Potential in Brazil • Species with proven technology (breeding, feeds) • Adapted to brackish systems • Seedstock supply • Replacement in shrimp ponds (Thailand, Australia) Acknowledgements: Fenacam organizing committee Mainstream Aquaculture Pty Ltd for providing some slide material.
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