Fish aquaculture (2)

Question 1

Ghalyoun farm

Answer 1

has 4.000 Fedon and it should increased to 9.500 Fedon (Fresh water because Egypt don’t have marine aquaculture)

Question 2

Species

Answer 2

Nile tilapia
Blue tilapia
Mugil Capito (طوبار)
Mugil cephalus (بوري)
Common carp (مبروك)
Grass carp (مبروك)
Silver carp
Sea Bass (قاروص)
Sea bream (الدنيس)
Penaeus Japonicus (جمبري)

Question 3

Nile tilapia VS Blue tilapia

Answer 3

Nile tilapia
The bands in caudal fin terminate with the end of fin

Blue tilapia
The bands in caudal fin terminate before the end of fin

Question 4

Mugil cephalus

Answer 4

Has broadhead and has adipose flip on eye pupil

Question 5

Common carp

Answer 5

Scattered scale

Question 6

Carp family

Answer 6

Has lower palatability compared to tibia and they are fatty fish

Chinese origin

Question 7

Grass carp

Answer 7

Diffuse scale

Question 8

Silver carp

Answer 8

Has no teeth and fed on algae by suction

dorsal fin not divided

Spines are not classified in young and deposited inside flesh

Has lateral line

Question 9

Sea Bass

Answer 9

carnivorous fish so it has teeth with terminal mouth

anterior and posterior dorsal fin

it’s marine water and adapted to burkes water and fresh water but with less growth rate

Question 10

Penaeus Japonicus

Answer 10

White leg shrimp or litopeanus vonnmei which is not native but it has a huge advantage which is it can adopt on different levels off salinity and it can live in freshwater without any effects on its growth which will help us to produce it in deserts , It has two types salt shrimp and sweet shrimp

Question 11

Aquaculture Systems (Diverse and complicated)

Answer 11

1. Intensity & Density
2. Culture
3. Structures
4. Farm integration
5. Species stock for farming
6. Water exchange

Question 12

Intensity & Density

Answer 12

Extensive - intensive – semi intensive

Question 13

Culture structures

Answer 13

Ponds - Tanks - raceways - cages - pens racks - long lines and floats

Question 14

Farm integration

Answer 14

Integration of aquaculture

Question 15

Species stock for farming

Answer 15

Monoculture - Polyculture

Question 16

Water exchange

Answer 16

Open - static - semi closed - recirculation

Question 17

Intensity & Density

Answer 17

Species and group difference → (depend on Marketable size)

Tilapia in RAS (recirculation) and shrimp in ponds

Tilapia has large size , if I want to produce shrimp (50 shrimp/m) I will not need filters but if I want to produce Tilapia at the same size I will need filters and it must be recirculating system

Question 18

Natural ecosystem in sea

Answer 18

Top Predators → Small Fishes → Zooplankton → Phytoplankton

Question 19

Zooplankton

Answer 19

Animal origin

Fed on Phytoplankton

Question 20

Phytoplankton

Answer 20

Plant origin

Consuming CO2 and producing O2 by Photosynthesis

85% of O2 source

Question 21

Extensive (متوسع)

Answer 21

Low Fish density

High natural food

Low Formulated food

Question 22

Semi Intensive (شبه مكثف)

Answer 22

Moderate Fish density

Moderate natural food

Moderate Formulated food (supplement)

Question 23

Intensive (مكثف)

Answer 23

High Fish density

Low natural food

High Formulated food

Question 24

Extensive feeding

Answer 24

Natural food

Question 25

Semi Intensive feeding

Answer 25

Natural food + Supplements

Question 26

Intensive feeding

Answer 26

Artificial food

Question 27

Why Intensive is risky system (Intensive disadvantages)?

Answer 27

1. High inputs
2. Large water requirement and I should exchange it regularly (Filters are not enough)
3. High mortality rate and decline growth if I don’t clean water (↑ ammonia)

Question 28

Why I must use artificial feed in intensive system ?

Answer 28

1. Natural feed source is phytoplankton which is need fertilizers to grow up and do its Photosynthesis role , so if I exchange water regularly , the fertilizers will haven’t enough time to grow up and the phytoplankton will not grow up also
2. The fertilizers decomposition will increase ammonia level because its organic matters

Question 29

The organic matters (fertilizers) is …. by fish

Answer 29

not digested

Question 30

Intensive aquaculture

Answer 30

1. Extremely high stocking density (much higher than would ever be found in natural systems)
2. Extra environmental control (i.e. temperature, dissolved oxygen, lighting, water quality requirement)

Question 31

Intensive systems

Answer 31

Ponds
Cages
Raceways
Tanks

Question 32

Ponds

Answer 32

Shrimp & tilapia with water exchange & padel aerator

Question 33

Cages

Answer 33

Tilapia , Capito , Cephalus , silver carp & sea base and sea bream in Mediterranean

Question 34

Raceways

Answer 34

Trout species , Narrow long structure has a source of correct water

Question 35

Tanks

Answer 35

Eels in japan

Question 36

A complete over environmental conditions within the system

Answer 36

• Mostly , intensive systems are indoors so that climate control does not have to be maintained for each individual system (e.g. or raceway)
• High degree of control required, aeration and water retreatment systems are sophisticated
• Skilled technicians to monitor and maintain them
• Automatic generator

Question 37

Intensive systems are …..

Answer 37

indoors so that climate control does not have to be maintained for each individual system (e.g. or raceway)

Question 38

A properly designed and maintained intensive aquaculture system

Answer 38

the highest yield per unit volume or space of any aquaculture system

However ; might be Risky and Expensive