Aquatic Animal Production Flashcards
What is Aquaculture
Farming of aquatic organisms, including fish, molluscs, crustaceans and aquatic plants
How are the types of aquaculture systems divided and give examples
By water type - freshwater, marine, brackish water productions
By the nature of the system - ponds, cages, raceways, recirculating aquaculture systems (RAS)
What are the 4 basic requirements for a aquaculture system
Water
Oxygen
Food
Waste disposal
Describe the basic production cycles of aquaculture
Broodstock => hatchery => grow out => slaughter => back to broodstock
What is meant by smoltification and what fish does this occur in
Smoltification = change in body colour and gaining the ability to survive at sea
Species - salmon
Name the steps in aquaculture of molluscs
Production of seed (eggs)
Juvenile nursery culture
Grow-out of sub-adults to harvest size
How do pond systems provide oxygen and remove waste
Rely on natural processes
Name the types of cages that can be used
Circular or square
Variable in size
Soft or hard
Freshwater or sea
Name the advantages and disadvantages of a cage system
+ve - easy stock, feeding and harvest
-ve - little environmental/water quality control, shared water body (quicker spread of disease)
Name a disadvantage of a raceway system and how they try to combat this
Water flows straight from one subunit to another, not good from a biosecurity point of view
Fish receiving the freshest water are the youngest, ones at the bottom of the farm are the most immunologically robust
Name some species of fish that are raised in a cage system
Salmonids, sea bass, tuna, sea bream
Name some species of fish with are raised in a raceway system
Trout, carp, prawns
Name the advantages of a recirculating aquaculture system (RAS)
Can be located most places
Less water requirement as water is cleaned and recycled through the farm
Name the disadvantages of a recirculating aquaculture system (RAS)
Recirculating water can magnify and pathogen challenged
Fish must be screened for disease
Significant energy input
Expensive
name some species of fish raised in a RAS
Salmon, trout, sturgeon
Why welfare in aquaculture is important
Ethical considerations
Quality of fish
Good welfare conditions => less stress and disease susceptibility => less dependence on medication/treatments => better growth rates and food conversion => better-quality product!
Name the 2 main pain processes in fish
Nociception
Conscious recognition - unclear in fish
What is an OWI when talking about assessing welfare in fish farms, and what are the 2 categories
OWI = operational welfare indicator
2 categories - direct or indirect, individual or group based
Give some examples of indirect OWI’s (x5)
Water quality parameters
Lighting
Feed quality
Stocking density
Tank microbiome
Give some examples of direct OWI’s
Group-based: mortality, behaviour, appetite, growth, disease
Individual: body condition, fin condition, eye condition, gill condition, sexual maturation
Are invertebrate decapods protected under animal welfare act 2006
No
e.g. crabs, lobsters, prawns
Name 3 impacts of aquaculture on public health
- Hazards to the public from farming in shared aquatic environments (water pollution)
- Hazards from eating aquatic products (food borne diseases)
- Zoonoses
How can water bodies impact on antimicrobial resistance
Allows easy mixing of bacteria
There is an overuse of antimicrobials in countries where veterinary controls are poor
Name some non infectious contaminants which can affect people eating aquatic products
Veterinary residue contamination
Herbicide or pesticide contamination
Heavy metal contamination
Biological toxins
Name the pathogenic bacteria which are food/waterborne
Clostridium botulinum serotype E
Vibrio parahaemolyticus
Salmonella spp.
E. coli
Listeria monocytogenes
Name a pathogenic virus which is food/waterborne
Norovirus
Name 5 bacterial zoonotic diseases from fish
Aeromonas spp.
Vibrio spp.
Mycobacterium spp.
Streptococcus iniae
Erysipelothrix rhusiopathiae
Name 3 types of parasites which pose zoonotic risk from fish and give an example of each
Trematodes - Heterophyidae or Opisthorchiidae
Nematodes - Anisakidae and Gnathostomidae
Cestodes - Diphyllobothridae
