Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
27 Cards in this Set
- Front
- Back
|
Describe the fresh water phase of salmon development? |
Broodstock stripped of their eggs and milt in late autumn/early winter. Fertilised eggs hatch in freshwater nurseries. Alvin with yolk sac attached grow into parr in raceways, nets of tanks. Parr undergo a metabolic change at 40 g to become smolts. Smolts are transferred to the sea for on growing usually in spring/summer |
|
|
Describe what happens during the marine phase of salmon farming? |
Smolts grown to the size of 4-6 kg. In nets or cages. |
|
|
How are salmon monitored in the marine phase and fed? |
Mechanically fed and remotely monitorred. |
|
|
When may fish be handled during the marine phase? |
Remove early maturing grisle. Maintain stocking density and average size. |
|
|
What is the stocking density of a salmon net? |
15-25 kg per m3 |
|
|
How long does it take to produce harvested salmon? |
It takes 1.5-2 years. |
|
|
What is the problem with net cages? |
Open to the environment. No environmental control. |
|
|
What can we not do in the marine phase? |
Exclude pathogens |
|
|
Name 2 species of sea life causing problems in fish populations? |
Lepeoptheirus salmonis. Caligus elongatus. |
|
What are clinical signs of sea lice in salmon? |
Observed as increase in activity fish jumping above water. |
|
|
What are problems with sea louse control with infeed medication and bathing techniques? |
Environmental impact. Legislative restrictions. Resistance. |
|
|
What is polyculture? |
Cultivating different species of fish together who don't contest for food etc. Wrasse, salmon, lumpfish. |
|
What is the sea lice treatment of the future? |
Using cleaner fish like wrasse to eat the parasites. New locations- fallowing. New medical treatments and aids. Optimising treatments. RAS/enclosures. Husbandry and mangement developments. |
|
|
What are the main viruses of atlantic salmon? |
Infectious Pancreatic Necrosis. IPN Pancreatic disease. PD Infectious Salmon anaemia. ISA. Gill pox virus. Cardiomyopathy syndrome PMCV |
|
What is the issue with vaccinating fish for viruses? |
Yet to proven effective. |
|
What is the aetiology of pancrease disease? Pathogenesis? |
Alphavirus. Causes complete necrosis of pancreatic tissue and or myopathies of skeletal muscle and heart. |
|
Signs of pancrease disease? |
Found dead, often at feeding. Periods of inappetence. Chronic ill thrift get runts and loafter. Secondary louse infestation. |
|
|
How can we control and prevent pancreas disease in salmon? |
Impact less if exposed to virus during a period of starvation. Vaccination and feeding strategies. |
|
|
What happens on a farm with Infectious salmon anaemia? |
Slaughter with no compensation. A notifiable disease. |
|
|
Bacterial infections of atlantic salmon? |
Aeromonas salmonicida. Listonella. Vibrio Anguillarum. Vibrio salmoncida. Moritella viscosa. |
|
What is the major bacterial cause of disease in fish? Name the bacteria and what it causes? |
Furunculosis caused by Aeromonas Salmoncida. Septicaemia of fish. |
|
|
How was Furunculosis treated in fish? |
Antibiotics in feed. AMR ! |
|
|
How can vets help in salmon industry for major production limiting diseases like furunculosis? |
Programmed sensitivity testing. Early intervention. Strategic treatments. Vaccine development and use. |
|
What are vaccine associated problems with fish? |
Difficult to administer. Intra-abdominal adhesions. Melanisation. |
|
|
What are the pain objectives when faced with a fish disease problem? |
Lessen the stress of the fish: Decrease feeding. Increase oxygenation. Minimize handling. Reduce effects of temperature. Reduce spread of infection: Remove moribund and dead fish. Increase farm hygiene and bio security. |
|
|
What is a major cause of disease in fresh water broodstock, eggs and alvins? |
Fungal disease saprolegnia spp. |
|
|
How can we ensure gill health? |
Freshwater and hydrogen peroxide. Changes to fish husbandry practices. Gill medicines |
