The life cycle of

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The life cycle of farmed salmon
A presentation from www.laksefakta.no
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List of contents

• 1. Facts about salmon production
• 2. The life cycle of salmon
• 3. Fish feed
• 4. Fish farmer a responsible job
• 5. Harvesting
• 6. A popular globetrotter

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1. Norways major farm animal

• Everyone knows about life on a farm. Very
• few know anything about life on a fish farm
• Salmon is our most important farm animal,
  measured both in tonnes and numbers
• Norway produces twice as much salmon as beef,
  mutton and pork combined
• In 2004, Norway produced around 540,000 tonnes of
  salmon

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2. The salmons life cycle

• All farmed salmon originate from brood stock and
  are reared on special farms
• Todays brood stock originated from 40 Norwegian
  salmon strains, which were collected in the early
  1970s
• Since then, salmon have been bred so that they
  are as suitable for farming as possible

Photo Norwegian Seafood Export Council
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Fertilisation

• The brood stock are stripped in the autumn and
  spring. Eggs and milt are removed from sexually
  mature salmon
• Fertilisation is done by mixing the eggs, milt
  and water. The mixture is then placed in an
  incubating system
• During incubation, water temperature is kept
  stable and the water is replaced regularly
• Newly fertilised eggs must be left to lie
  undisturbed in the dark to mimic the river bed

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Eggs

• After around 30 days the eyes of the embryo
  salmon can be seen as two black spots in the egg
• At this stage the eggs may be sorted and
  transported to other facilities
• The temperature determines the length of the
  incubation period
• In water at 8C, incubation takes approx. 60 days
  from fertilisation until the egg hatches

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Sac fry

• The fry are not yet fully developed when they
  hatch
• They get their nourishment from a yolk sac
• The fry must be left undisturbed with good
  support for the yolk sac. If it tips over they
  may die
• When the yolk sac is almost depleted, the fry are
  moved from the incubators into larger tanks

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Weaning

• Weaning is a critical phase for salmon, as it
  must learn to eat
• Wild salmon have a high mortality rate. In salmon
  farming this is less than five per cent
• When weaning has started, the fry begin to move
• The fish are usually exposed to light 24 hours a
  day, just like the wild salmon in Northern Norway
  in the summer. This gives faster growth

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Young salmon (parr)

• When the yolk sac is depleted, the fish develop
  dark markings along their flanks so-called parr
  markings
• The salmon are now called parr and are kept in a
  freshwater farm
• The salmon parr continue to grow in tanks up to
  smoltification
• During smoltifcation the salmon undergo
  significant physiological changes in order to be
  able to live in saltwater

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Smolt in the sea

• After approx. one year in the freshwater farm,
  the fish are ready for release into sea cages
• The salmon are usually 80100g on release and are
  now called smolt
• The fish are transported in fish carriers (well
  boats) to the sea localities
• Smolt are transferred from freshwater to sea
  water in the spring and autumn

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The sea farm

• In the sea, adult fish live in net enclosures
  called cages
• The fish farmer keeps a careful eye on the
  salmons development and environment
• The salmon are kept in the sea until they reach
  approx. 4 kg
• The production period is from one to two years,
  depending on the time of release, size and
  temperature

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3. Feeding

• Automatic feeding systems are the most common
  method of feeding the salmon
• A feeding system consists of a feed silo, hoses
  from the silo and a small computer that controls
  feeding
• The farmer also feeds manually, when required and
  also to keep an eye on life in the cages
• The fish are fed different types of feed
  depending on size, season and growth

Photo Norwegian Seafood Export Council
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Composition of the feed

• All fish feed is healthy and safe both for the
  salmon and for those eating the salmon
• The feed mainly consists of natural ingredients
  such as fatty acids and amino acids from fish
  oil, fishmeal, vegetable oils and protein, and
  minerals and vitamins
• Astaxanthin in the feed ensures that the fish
  absorb enough vitamin A and it gives the meat its
  characteristic pink-red colour. In the wild the
  salmon gets astaxanthin from small crustaceans
• Antioxidants are added to the feed to prevent it
  from becoming rancid

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4. Fish farmer a responsible job

• Much of the work on the fish farm is automated,
  but good fish farmers are still worth their
  weight in gold
• Like other farm animals, salmon depend on
  receiving good human supervision and care
• Feeding is the most important task of the fish
  farmer
• The fish farmer is responsible for the daily care
  of the fish and for their health and hygiene.
  Some of the routines are compulsory by law

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Well regulated husbandry

• The Norwegian Food Safety Authority regularly
  controls the health and welfare of the fish
• All farms are obliged to have a fish welfare
  service, which is inspected six times a year
• In addition, a public veterinarian visits the
  farms twice a year
• Salmon farming is regulated according to a number
  of acts and regulations, which protect the
  welfare of the fish

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5. Harvesting and processing

• All harvesting is reported to the Norwegian Food
  Safety Authority
• The fish are transported in a fish carrier (well
  boat) to the harvesting plant, where they are
  stunned or made brain dead by other means
  according to governmental requirements, before
  being bled and gutted
• The salmon are cleaned, graded as superior,
  ordinary and production according to size and
  quality and then packed in cases for export or
  further processing. Export of production fish is
  prohibited

Photo Norwegian Seafood Export Council
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6. Popular globetrotter

• Norwegian salmon is exported fresh, frozen or
  processed to more than 100 countries
• It is served as sushi in Japan, lucky fish in
  China and as festive food in Russia
• Russia, EU and Japan are the most important
  markets
• All salmon is tagged with the harvesting date,
  harvesting plan, species and the name of the
  farm. This ensures good traceability

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Healthy, safe and trendy

• Health experts around the world recommend
• that people eat more seafood and especially
• oily fish such as salmon
• Salmon is the favourite fish of young Norwegians
• No other fish in the world is subject to such
  extensive control as Norwegian salmon
• Producers and the authorities have a
  comprehensive system to ensure that salmon
• is safe food

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Would you like to find out more?

• Visit www.laksefakta.no
• Articles on salmon and aquaculture
• Presentations (ppt) and fact sheets
• Free key rings
• Delicious salmon recipes

Use of the photographs in this presentation for
other purposes is prohibited.