List the 10 pillars
Big numbers
Biggest vertebrae group
Different feeding/environments/behaviours/sizes
Jaws
Their presence
Agnati
Gnatostomi: Condroitti/osteitti
Gut length
Length
Stomach size
Feeding behaviour
Anatomy of the digestive system
Food choice
Most species - omnivorous-carnivorous
Feed formula, aggressiveness, cannibalism, feeding techniques
Well fed
Behaviour/tank balance/nutrient profile/reproduction activity
Warm works
Ectotherms, ↑ t, ↑activity
Affects feeding/reproduction/biofilter
Gills
Breathing and excretion
Top breathers
Countercurrent flow of blood and oxygen through gill lamellae
Ammonia
Toxicity/biofilter/ecosystem balance
Reproduction strategies
Mostly ovuliparity
Are all fish ectotherms?
Most of them are
Another name for ectotherms
Poikilotherms
What are Stenotherms?
They regulate their body T y inhabiting constant-T environments
Vulnerable to environmental changes
Their organisms operate in a small T band
Also sensitive to pH, light, oxygen, etc
What is the name for fish that can:
function at a wide range of temperatures
Adapt to environmental changes
Organisms operate at different environmental Ts
Eurytherms
Which regulatory type's reproduction can be induced by changing water temperature?
Stenotherms
(Eurytherms need more stimuli - feeding/size)
List considerations for stenotherm fish
Constant transport T - heating pads-packs
Careful tank acclimation
Constant tank environment
Reproduction can be induced by T
How does Oxygen move in the gills?
By diffusion - never stops
From HIGH pressure regions to LOW pressure regions
Countercurrent flow
The equilibrium never reached
Almost all Oxygen diffuses into the blood
Which type of fish does the following:
Actively uptakes salt from the environment by mitochondria-rich cells(gills,skin(?)), making water diffuse into the fish
Excrete large amount of a very hypotonic(dilute) urine to expell the excess water
Doesn't drink
Internal salinity around 10%
Freshwater fish
List features of osmoregulation in a marine fish
Internal osmotic concentration lower than that of the surrounding seawater
Actively excretes salt from the gills
Water enters by osmosis
Produce small amount of very concentrated urine
Drinks seawater
Tend to lose water - from skin
Which fish has isotonic bodies with the environment/don't control their osmolarity?
Osmoconformers
Some marine animals(cartilaginous fish)
Internal salinity 35%
Are most fish stenohaline or euryhaline?
Stenohaline - salt or fresh water strictly
What is the feature of euryhalines?
Can effectively osmoregulate across a broad range of salinities
What do catadromous fish do?
Reproduction in the sea, feeding and growth in the rivers
The opposites are called Anadromous
Who carries out nitrosation?
Nitrosomonas spp
What do Nitrobacter spp do?
Carry out Nitrification
From nitrite(NO2-) to nitrate(NO3-)
How does bacterial oxidation of ammonia go?
Nitrosation: NH3 →NH4+ → NO2-(nitrite)
Nitrification: NO2- →NO3-(nitrate)
How often should the water be changed?
Every 50 days
What size of particles do the mechanical filters remove?
Particles larger than 40-60 microns
What are the functions of a fixed bed biofilter?
Metabolic waste → Nitrate
Removed particles <40-60 micron
What is the function of an ozone chamber?
Cleans water by oxidation
Enchances flocculation of microparticles
Neutralizes the microorganisms
Controls off-flavour levels
What is the purpose of CO2 degassing?
Removal of CO2 and free Nitrogen
What is a RAS system?
Recirculating aquaculture system
List the steps of RAS
Oxygenation(low pressure)
Optimal water velocity
Mechanical filters
Biofilters
Ozone chamber
CO2 degassing
What is the optimal surface of bio balls?
1500 m2/m3
How much time does the biofilter require to work effectively?
About 2 months
Which bacteria develop from 30 to 60 days in a biofilter?
Nitrobacter spp.(nitrites to nitrates)
In what time period do Nitrosomonas spp. populations start to develop and transform NH3 to nitrites?(NO2-)
During the first 30 days
What organic fertilizers are used to start-up the biofilter?
Ammonium nitrate
How often does the substrate of the biofilter needs to be cleaned?
Every 2-3 months
Oversize of biofilter of about 10-20%
Name 2 top exporters
Asia
South America
Name 3 importers
Europe
UK
USA
What does Anadromous mean
Fish that spend most of their adult lives at sea, but return to freshwater to spawn
Name the fish that spend most of their adult lives in freshwater, but return to saltwater to spawn
Catadromous
What is Gonochorism?
Two different genders, no changes throughout the life
What are the 2 types of hermaphroditism?
Simultaneous - both gender organs at the same time
Sequential - can change sex
What is a recommended size for an outdoor enclosure per one Flamingo bird?
1.4 m^2
Last changeda year ago