Objective 16.06

1
Objective 16.06

• Compare types of production aquaculture systems
  and their utility in efficiently producing
  aquaculture food products.

2
Aquaculture
3
Aquaculture

• the controlled production of animals that
  normally live in water (fish farming)
• three thousand year old practice started by the
  Egyptians and Chinese

4
Aquaculture

• commercial growing of fish
• five million tons a year produced
• demands of the consumer has increased

5
Aquaculture

• fish provide a high quality high protein supply
  of meat

6
Aquaculture

• aquatic animals are produced efficiently and
  economically
• fish account for 12 of the meat consumed in the
  US

7
Fish Production

• many advantages over other agricultural animals
• 9 pounds feed for 1pound of gain for steer
• 2 pounds feed for 1 pound of gain a fish

8
Fish Production

• fish have a higher percentage of edible meat (up
  to 85)
• up to 6000 pounds fish can be raised on one acre

9
Fish Production

• fish are ectothermic (cold-blooded)
• this means less energy goes into maintaining a
  constant body temp

10
Aquaculture

• two types of water creatures
• freshwater
• saltwater

11
Aquaculture

• animals raised for production may include
• crustaceans (shrimp and crayfish)
• mollusks (clams and oysters)
• amphibians (frogs)
• reptiles (alligators)

12
Aquaculture

• Trout raised where there is cold running streams

13
Aquaculture and Management of Fish Production

• Hatcheries supply fry or larvae to units for
  fingerling production

14
Cage Culture

• Cage culture contains the aquatic animals or
  plants in a small area of a pond
• Fish can be monitored better for growth rates and
  feeding purposes
• Water quality must be monitored to insure that
  the fish are not stressed or killed since fish
  can not move to another section

15
Cage Culture

• Roll over condition where a ponds water
  quality suddenly changes during certain weather
  conditions
• Roll over results when less-oxygenated water is
  brought to the surface.
• low levels of dissolved oxygen cause fish to die

16
Cage Culture (Continued)

• Dissolved oxygen levels in any fish system can
  become so low that fish die
• Dissolved oxygen levels are lowest in early
  morning
• Aerators are used to improve oxygen levels during
  dry hot periods

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Fish Respiration

• breathe oxygen
• use gills to take oxygen from the water and put
  it to use in the bloodstream
• gills act just as lungs do

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Fish Respiration

• The oxygen is put into the water through
• photosynthesis
• process in which aquatic plants which releases
  dissolved oxygen into the water

19
Water Quality

• Must be closely monitored when recirculation
  tanks are used to raise fish
• Recirculation tanks process waste water through a
  biological filter and return it to the growing
  area

20
Managing Aquaculture

• Management difficulty is directly related to the
  density of fish in the system

21
Fish Production

• Problems in fish production
• dissolved oxygen level must be maintained
• shipping the meat (fish spoils quickly)
• operations are labor intensive
• operations are high risk