PROGRESS IN HATCHERY TECHNOLOGY OF COBIA Rachycentron canadum AT THE
UNIVERSITY OF MIAMI EXPERIMENTAL HATCHERY
Refik Orhun*, Daniel Benetti, Ian Zink, Philippe Douillet, JamesCollins, Patrick Rice, Bruno Sardenberg, Fernando Cavalin, Roger
Kirkpatrick, Donald Bacoat, Bristol Denlinger
Outline
- Maturation- Extensive Production of Fingerlings
- Preliminary Fingerling Shipping Trials
- Juvenile Feeding Trials
- Intensive and Semi-intensive Fingerling production
- Conclusions and Directions for Future Research
Maturation
Keys to Broodstock Fish Management:- BioSecurity
- Capture, Transport, and Survey
- Prophylactic Treatments
- Recirculating System
- Feeding and Temperature Regime
Extensive Production of Fingerlings
- Pond Preparation: Cleaning, Filling, and Fertilization
- Stocking
- Water Quality and Plankton Dynamics
- Supplemental Feeding
- Growth and Size at Harvest
Yolk-sac larvae - 1 day old
Growth in Pond Culture
10 days old 20 days old
2 days old
- Temperatures between 30 to 32ºC - N03-N, PO4-P, and Meta-silicate- Stocking of fish two days after filling- First feeding on tintinnids and other large ciliates, no rotifers- Additions of Artemia nauplii beginning at day 5- High density of adult copepods after two weeks- Ample supply of aquatic insects, i.e. waterboatman
Fingerling Shipment Trial
- Temperature- Size- Biomass density (kg/m3)- pH and NH3 Control- Pre-Shipping Prophylactics- Probiotics
Parameter Units Box 1 Box 2 Box 3 Box 4Wet weight (g) 3.2 3.2 2.5 2.3Total length (mm) 96.2 98.1 89.5 91.4Age (days) 45 45 43 43Biomass density (kg/m3) 5.5 5.7 2.5 2.8survival (%) 97% 97% 100% 100%Temp. start [C] 18.0 17.8 18.0 17.8Temp. end [C] 20.4 20.2 19.5 19.0O2 start (mg/l) 24.4 24.7O2 start (%) 350 352O2 end (mg/l) 11.8 12.7 15.8 15.0O2 end (%) 162 173 212 200pH start 7.7 7.8 7.5 7.5pH end 7.2 7.3 7.4 7.6Probiotics 103cells/ml Yes NoFormalin (1h) 100ppm Yes No
Juvenile Feeding Trial- Objective: Evaluate Ziegler’s Marine Fish Diet- Nursery Cage Size Fish: 8.7-30g
y = 3.4x - 27 r2 = 0.88
100
120
140
160
180
200
220
240
260
50 55 60 65 70 75 80
Age (dph)
y = 3.9x - 80 r2 = 0.95
100
120
140
160
180
200
220
240
50 55 60 65 70 75 80Age (dph
y = 0.1787e0.08x r2 = 0.9
0
10
20
30
40
50
60
70
80
90
50 55 60 65 70 75 80Age (dp
y = 0.6429e0.0677x r2 =
0
20
40
60
80
100
120
140
50 55 60 65 70 75 80
Age (dph
Juvenile Feeding Trial ResultsB-1 C-2
Age weight ration growth biomass weight ration growth biomass(dph) (g) (% bywt/d) (%/d) (kg/m3) (g) (% bywt/d) (%/d) (kg/m3)
52/53 23.5 7.3% 11.1 10.7%59 34.7 4.7% 0.065 1.11 20.3 5.9% 0.087 0.3666 59.1 6.1% 0.076 1.03 39.9 5.5% 0.096 0.6974 95.8 3.8% 0.060 0.96 62.2 3.2% 0.055 1.16
Overall Growth 307% 461%FCR 0.55 0.71Gross growth conv. efficiency 36% 28%
y = -0.0415x + 0.11 r2 =
0.04
0.05
0.06
0.07
0.08
0.09
0.10
0.20 0.40 0.60 0.80 1.00 1.20 1.40
Biomass density (kg/m3)
Intensive and Semi-intensive Larval Rearing andFingerling Production
Conclusion
- Cobia hatchery technology of spawning, and production of fingerling in extensive ponds and intensive tanks
- Microbial management of live feeds via probiotic bacteria- ERGONOMIC HATHCERY !- Prophylactic treatments and fingerling transport
Directions for Future Research- Year-around spawning and fingerling production
- Definition of the microbial environment w/ and w/o probiotics
- Extension of probiotic regime into the pellet feeding stage
- Cannibalism and grading
