Innovations and Georgia
Aquaculture
Gary J. Burtle
Animal & Dairy Science
The University of Georgia
www.cpes.peachnet.edu/aquaculture
Hybrid Catfish Project
• Interest in Hybrid Catfish is gaining ground
in the Southeast U.S.
• Selling for 1.25 to 3.0 cents per inch
depending on state and quantity
• Highest prices in Alabama
• Limited by fingerling availability
Spawning Hybrids
• Need 5 yr old blue males, 4-5 year old channel
females
• Check females each week during spawning season
and inject with carp pituitary
• Inject male blue catfish with carp pituitary and
dissect testes for in vitro fertilization after female
is stripped of eggs, 3-5 females per male
• Expect 3,000 to 4,000 fry per female
Hybridization Trial Results
• 50% of females will produce eggs by
stripping after hormone injection
• Male blue catfish can be stimulated with
urine from female blue catfish
• Harvest testes within 24 hours of
stimulation, urine or hormone
• Maintain 78 degree water for best results
Hybrid Stocking
• Obtain hybrid fingerlings from hatcheries
with disease control programs
• Have fingerlings inspected for disease prior
to purchase
• Apply chelated copper rather than copper
sulfate for hybrid ponds
• Stock 6,000 to 10,000 per acre
• 0.05 to 1.5 pounds in 5 months
Vietnamese Catfish
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Basa, Pangasius bacurti
Grown in cages on rice bran and dried fish
Sold as frozen fillets
From 7 million pounds in 2000 to over 20
million pounds in 2001
• Illegal label until October 2001
Basa
Cage Culture of Basa
National Bill Sets Label Law
• Introduced in House in early 2001 passed
Senate in October
• Requires “catfish” to be from the family
“Ictaluridae” and excludes “Siluridae” or
“Pangasiidae”
Status of Imported Catfish Label
• Basa fish sold as catfish perceived as illegal
• July 2001, Vietnam orders all basa labelled
as product of Vietnam, Mekon catfish, basa
catfish, or pangas catfish.
• October 2001, US Senate passes label law
to require proper catfish labeling
Impact of Vietnamese Catfish
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20 million pounds of fillets in 2001
23% of farm raised catfish fillet market
3% of US catfish market
Competition at time of US economic
recession
• Pond bank price below 50 cents per pound
in Mississippi, 53 cents in Georgia
Fish Imports (1,000 lb)
Catfish
Fillet
Sept
2000
Sept
2001
Jan-Sep
2000
Jan-Sep
2001
615
1,401
5,174
12,175
5,552
40,787
50,007
Tilapia
7,499
Products
Cold Storage Holdings (1,000 lb)
Down 8 to 13% since 2000
10-31-00
10-31-01
9-31-01
Catfish
12,906
11,873
13,337
Saltwater
Total
278,085
240,879
240,713
Fresh Fish Prices at Fulton
Market (Nov 30, 2001)
Catfish Fillet
$ 2.75 /lb
Cod Fillet
$ 4.00 /lb ($2.00 frozen)
Tilapia Fillet
$ 3.90 /lb
Hybrid Striped Bass
Fillet
$ 2.75 /lb
Tilapia Culture
• Several Recirculating Systems in Georgia
• Some small hydroponics systems also in
Georgia
• Processing in North Carolina by Southern
States Cooperative
• Systems are in a 45-50 mile radius of
Valdosta
Economics of Tilapia Culture
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Based on capital provided by others
Must have land and positive net worth
Must be identifiable as a farmer
Approximately $20,000 net per year per
system as a goal
• Only available through Southern States
Cooperative
Freshwater Prawns
• Machrobrachium
rosenbergii
• An exotic shrimp from
Malaysia
• Tropical
• Lives in freshwater for
part of its life-cycle
U. S. Prawn Culture
• Of interest for over 25 years
• Limited by the availability of seed stock
• Cultured in Texas, Kentucky, Mississippi,
South Carolina, Tennessee, recently in
Georgia
• Average production 500 to 800 pounds per
acre.
• Maximum production about 2,500 lb/A.
Prawn Production in Ponds
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Prepare pond for stocking
Stock 10,000 to 30,000 juveniles per acre
Fertilize for first 30 – 60 days
Feed a sinking feed during months 2-4
Monitor and control oxygen and pH
Use narrow ponds less than 2 acres in size
Harvest before water falls below 60 degrees
Proper Sized Juvenile Prawns
• 60 day old, 95/oz
• 28-35 day old, 250 to
280 per oz
• Uniform size very
important
• Careful handling and
stocking are essential
to juvenile survival
• Avoid overcrowding
Feeding Prawns
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Start with cottonseed meal and N-P-K
Use sinking catfish feed for 500 to 800 lb/A
Use shrimp diet for higher yields
Monitor zooplankton with net during first
month
• Feed over entire pond area
• Estimate feed rate based on prawn samples
Water Quality in Prawn Ponds
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Aerate continuously
Keep oxygen above 3.0 ppm
Monitor pH twice each day
Flush with water to keep below 9.0 (Use
pond water of low pH if possible)
• Add gypsum to lower pH, 1,000 to 2,000
lb/Acre added as needed
Harvest Procedure
• Seine most of prawns with water at 1/2
depth
• Use 1/2 inch mesh seine, grade with bar
grader, 62/64 width
• Consider partial harvest one month before
end of season
• Final harvest requires pond draining
Economic Sketch
• Breakeven at 1,000 lb/A is about $5.00 per
pound
• Juveniles cost $1,500 to $3,000 per acre
• Feed costs $300 to $550 per acre
• Aeration costs $200 to $400 per acre
• Labor cost $800 to $1,200 per acre
• Variable cost total$2,800 to $5,100 per acre
Litopenaeus vannamei
Conditions for Culture
• 0.5 to 2.0 parts per thousand salinity
• Recirculated water or small, aerated ponds
• Establish bacterial food source as well as
feeding an adequate sinking pellet
• Warm water temperatures would require
indoor culture in Georgia
• Indoor culture may prevent disease outbreak
Current Status of Perry Project
• Contact William MacGrath 478-988-0590
• Georgia Marine Shrimp Project
• Looking for Cooperating Farmers for Phase
2 of project
• Economics available in next 12 to 24
months