Cold Water Fish Farming Flashcards
Seafood contains all essential nutrients but what macros?
proteins, lipids, and carbs
Seafood contains all essential nutrients but what micros?
vitamins, minerals and trace elements
If there was a shift of consumption from red meat to fish what would be the advantages?
Saves land and freshwater, less agricultural runoff, reduces greenhouse gasses + deforestation and increased public health (to an extent)
What is the feed conversion of fish compared to chickens and pigs?
fish - 85%, chickens 30% and pigs 20%
Describe the charecteristic of altlantic salmon farming in cold water
- well established
- benthic eggs + larve
- pelagic adults
- anadromous
- large and well developed
- dry feed from start
Describe the charecteristic of halibut farming in cold water
- relatively new
- pelagic eggs and large
- benthic adults
- solely marine
- small and less developed
- live feed from start
What countries farm Atlantic salmon
Norway, Scotland, Canada, Chile, Faroe islands
What is the FW part of the salmon lifecycle?
- Adults spawn in FW (Oct-Dec)
- Produce eggs (5-7mm)
- Eggs form eyed ova
- Eggs –> alevin –> fry –> parr –> smolt
What is the SW part of the salmon lifecycle?
- Smolt move form FW to SW to feed
- After 3 - 5 years in SW migrate back t FW to spawn
- Become sexually mature in migration
What are the six steps in salmon farming?
- parr/smolts in tanks with light/temp manipulation (FW)
- Transferred to SW after 8-16 months
- Grow up to 2 years
- Salmon Harvested (after brood selection - best salmon chosen to reproduce future generations)
- broomstick back to FW and stripped of eggs
- Alevins (<10 degrees) in silos and trays
steps all repeated
Broodstock fish are kept in separate facilities, true or false?
TRUE
Describe the eggs stage in salmon farming
- femals stripped of eggs
- eggs ferrtilised with sperm from lots of males
Describe the embryonic stage in salmon farming
- Broodstock stripped in autumn and winter
- Hatching occurs around 8 degrees and stable water flow
- fertilised eggs are kept in the dark
- eggs ‘eye stage’ reached after 30 days
- eggs then transported and sorted
- hatching occurs 60 days after fertilisation
Why is it important that the larvae are resting during the yolksac phase?
so that they use all of the energy for growth and not movement
What happens in the salmon larvae become disoriented?
They become stressed and die
How do fish farmers story the salmon large from becoming disorientated?
use a strong substrate (astroturf)
What is the absorption of yolk dependant on in salmon farming?
temperature
What happens when yolk-sac absorption is completed in salmon farming?
the larvae are moved to larger start feeding tanks (dry feed to start)
What conditions are in salmon farms when they start feeding?
Increase temperature and continuous light
What are the temperatures at –
- fertilisation to day 2
- eye stage
- hatching stage
- during hatching
- yolk stage
- fertilisation to day 2 = 8 degrees
- eye stage = 10 degrees
- hatching stage = 14 degrees
- during hatching = 12 degrees
- yolk stage = 16 degrees
What qualities does the Pikot-scale research station have?
- Automatic feeding
- submerged light
- surveillance and controls
- slaughter transport
What depth and temp do halibut spawn?
300-1000m
5-7 degrees water
Describe halibut eggs?
small, pelagic larvae
When do halibut sexually mature?
5 - 10 years
how much can a habit weigh up to?
300kg
Where and for how long are the yolk scare larvae kept in halibut farming?
silos and for 50 days at 5 degrees
what happens once the halibut egg is fertilised?
it is incubated for 14 days at 5 degrees
how long are the halibut are in sart feeding tanks
60 days at 11 degrees
what live feed is used for halibut?
artemia or similar
how much do halibut weigh when they are taken to the slaughter house?
3kg
