Term
| Most commonly cultured salmoniod? |
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Definition
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Term
| Trout and salmon are raised for? |
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Definition
| sport fisheries and food. |
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Term
| Most important step in developing coldwater culture is... |
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Definition
| the availability of an abundant source of high quality cold water (stream, springs, or reservoir) |
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Term
Coldwater Cult
Constant flow rates |
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Definition
| should be at least 500-650 m^3/day/ton of fish prod |
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Term
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Definition
| should be equal to or greater than 150ppm as CaCo3 |
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Term
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Definition
| should be maintained between 10-20 degrees C |
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Term
Coldwater Cult
Dissolved Oxygen |
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Definition
| should be equal to or greater than 5-7 ppm |
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Term
Coldwater Cult.
Holding Facilities |
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Definition
- earthen ponds
- raceways
- circular tanks
- cages and pens |
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Term
Cold H2O Cult.
Holding Facil.
Earthen Ponds |
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Definition
- Regularly shaped and arranged in a parallel fashion
- best in situations where disease are not prevalent
- fish raised here acquire benefits from eating natural foods
- concrete ponds have been used (easier to manage) |
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Term
Cold H2O Cult.
Holding Facil.
Raceways |
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Definition
- Easy to manage and maintain (can be self- cleaning)
- Require a water exchange rate of 4 volumes per hour
- Must be free of obstructions, have a uniform width and depth, be capable of separate draining, and have adequate aeration. |
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Term
Cold H2O Cult.
Holding Facil.
Circular Tanks |
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Definition
- Provide flexibility in that they can be used in many situations
- less water is required and have a uniform circulation
- considered self-cleaning
- best for holding fish from fry to fingerling stages, and for selective breeding |
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Term
Cold H2O Cult.
Holding Facil.
Cages and Pens |
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Definition
- used in both fresh and salt water
- must have plenty of water exchange in the cage
- stocking densities are often lower than other facilities
- cages must float and are equipped with feeders
- works well in remote areas |
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Term
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Definition
- some hatcheries raise and maintain brood trout (not salmon- they spawn in seasons by species after spending time in the ocean)
- most spawn annually (avg. female rainbow trout produces approx. 1,000 eggs per pound of fish)
- different strains of rainbow trout have been produced through selective breaking, allowing for spawning throughout the year |
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Term
Reprod.
Brood Fish (cont.) |
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Definition
Egg size & number varies with females at different ages.
- 3yr olds provide a higher % of eyed eggs resulting in larger and more rapidly growing fingerlings than do 2 yr olds
- egg size generally increases in females until they are 5-6years old, after which egg size decreases
- fingerlings growth is directly related to egg size, which is related to the age and size of the female brood fish. |
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Term
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Definition
| In nature, Rainbow Trout spawn from early winter to late spring. Spawning areas occur in riffles and are called redds. Female deposits eggs in redd and the male fertilizes eggs. No parental care. |
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Term
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Definition
With Salmon, fish are killed and gametes removed (they will die anyway)
- With trout, stripping is often used.
- must be done carefully to avoid fish injury
- fish are anesthetized with MS-222
- Female is grasped by the caudal peduncle and pectoral fin, held tail down over a pan, and gametes are extruded by applying pressure to the abdomen with the forefinger and thumb.
- not all eggs are removed to prevent internal injury
- timing is important to get "ripe" eggs |
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Term
Cold H2O Cult.
Reprod.
Cult. Spawning
Air Spawning |
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Definition
| used with trout. A hypodermic needle is inserted into the body cavity and air pressure is forced into the body cavity, which forces out the eggs. Air is eventually removed from the fish. This method removes more eggs and is faster than stripping. |
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Term
Coolwater Cult.
Includes sp like.. |
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Definition
-Striped Bass
- White Bass
- Hybrid Striped Bass
- Muskellunge
- Northern Pike
- Walleye
- Sauger
- Yellow Perch |
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Term
Coolwater Cult.
Striped bass & Hybrids |
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Definition
- adult brood fish are collected in the spring (approaching spawning time) using electrofishing or gills nets.
- Females are injected with Human Chorionic Gonadotropin (HCG) at 275- 300 IU/kg. Males are sometimes injected at 110-165 IU/kg to increase semen production. |
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Term
Coolwater Cult
Striped Bass and Hybrids cont |
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Definition
| after 20-28 hours females are catheterized to stage eggs. Eggs are examined under a microscope to determine stage of development and determine correct timing for spawning. |
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