Fish husbandry Flashcards
What groups are fishes are included in teleosts?
Carp, goldifsh, salmon, trout, parrotfish
What group are carps and goldfish in?
Cyprinidae
How do fish survive in frozen waters?
Antifreeze protein in blood
What types of reproduction can fish show?
Oviparous
Viviparous
Spawning in nests, fertilisation then egg depositor
Are fish monogamous?
Can be promiscuous, polygyny, polyandry, monogamy, some asexual
Which fish do not show sexual dimorphism?
Herrings
Anchovies
What are the 3 water salinities of fish?
Freshwater
Brackish
Marine
What are the 3 temperature ranges of fish?
Polar
Temperate
Tropical
Why is it very important to reduce stress and damage when handling?
Causes secondary infections
If a fish is suspected of an infection, what should be done?
Quarantine for 1-3 month s
Health check a sample of fish
Disinfection vital ,UV sterilisation
What are fish used for?
Ornamental
Experiments (2nd most used lab animal)
Aquaculture
How can fish be euthanised?
Overdose/rapid chilling if tropical
Co2 saturated water
Decapitation
Blunt force then severe spinal cord
What chemical can be used for euthanasia? What environments should this be done in?
Benzocaine
Bucket out of sight, water from system, same temperature
What temperature do rainbow trout (Oncorhynchus my kiss) require? What water do they require?
18 degrees
Fast flowing
Aggressive predators
Carp are tolerant to a wide temperature range. What water do they require?
Fresh
What salinity of water and temperature do sea bass require?
Marine or brackish
12 degrees
What water do mudskippers require? What do they require to prevent desiccation?
Brackish - although spend most of time on the beach
Humid environment
Males very aggressive
Where does metabolic waste come from in fish?
75% gills
25% urine
What happens to faeces and solid wastes as they decay in water? (Fish)
Decay to ammonia
Toxic to fish and clouds the water
What are the 3 sections of filtration?
Mechanical
Biological
Chemical
What is the purpose of mechanical filtration? Why is this important?
Prevent solid waste
Decomposes to ammonia, decaying uses oxygen, encourages pathogens, clogs the filter and fish girls
What bacteria cause mineralisation and decomposition of solid waste in fish tanks? How do they contribute to gunk?
Heterotrophic
Form thick layers themselves which clog the filter
What is the purpose of biological filtration?
Encourage growth of autotrophic bacteria
Breakdown toxic nitrogenous waste into harmless form
Describe the process of biological filtration of ammonia being converted to nitrates
Ammonia oxidising bacteria (AOBs) breakdown toxic ammonia to nitrate
Nitrite oxidising bacteria (NOBs) break down nitrite to nitrate
Nitrate less toxic
What do biological filters require?
Small amount of ammonia as food source Water Dark - inhibited by light Oxygen for oxidation Clean surface
Biofilters rarely need cleaning. What is a mucky bio filter the sign of? Why should they not be cleaned with tap water? What else can harm biofilters?
Inadequate mechanical filter
Chlorine in tap water kills bacteria
Antibiotics
What is the purpose of chemical filtration?
Adsorb undesirable substances from water
What are 3 examples of the compounds in chemical filters? What do they do?
Carbon granules - remove yellow colour
Zeolite - remove ammonia (freshwater only)
Phosphate removing granules - prevent algae
Why is efficient mechanical filtration important when using chemical filters e.g. activated carbon granules?
Solid waste blocks the pore of the media and prevents access to internal of granules
What are the 3 intensiveness systems of fish? Give an example of each
Open - caged environments in rivers, open sea etc
Semiclosed - rely on regular clean water to maintain water quality e.g. aquariums and trout raceways
Closed - water recycled in the system e.g. most aquariums, ornamental fish
