1. Topic: Topic: Prawn Culture Presenting to: Sir Waqas Ahmad
Shams Presenting by: Seema Hassan Sanam Taj Shagufta Siraj Ghani
Tabassum Malik
2. Introduction It is a crustacean Commercially it is known as
shrimp. In some parts like Chingri, Ghinga, Kolambi, Sungata,
Chemen, Shetli etc it is also considered as fish. Due to its nice
taste and delicacy it is served as food throughout the world.
3. Production In India prawn constituent 90% of the total
crustacean production. The most prawn production occurs in U.S.A
and secondly in India. Mostly prawns catches are made directly from
natural sources which largly include immature forms. Shrimp farming
is important because it is an important item of our export and the
annual foreign exchange returns range from 70-80 crores of
rupees.
4. Shrimp aquaculture in Pakistan In Pakistan the Indus delta
region has good potential for the aquaculture of marine shrimp.
There are about 385,000 ha of inter-tidal lands available which can
be converted into shrimp ponds at a very low cost. The Government
of Sindh has earmarked 6,400 ha of land for shrimp culture in
Thatta district. Unfortunately, this project was not successful
because of some administrative problems and natural constraints.
Some private parties also tried shrimp culture in this area, but
were not successful.
5. Natural Constraints To Shrimp Farming In Pakistan Salinity:
The salinities in the Indus delta creek reach as high as 45 ppt in
the dry season (unsuitable for shrimp culture) Temperature: The
other constraint is that of temperature. Most tropical penaeid
shrimp species grow best within a temperature range of 28 to 32C.
In such areas only one crop of shrimp in summer months can be
harvested as against two in other south east Asian countries.
6. Types of prawn Prawn inhibits all types of water i.e Sea
water Fresh-water Estuaries Their greatest quality lies in their
adaptation to changing factors like Temperature Oxygen
concentration salinity
7. 1. Marine Water Prawns The prawn caught from sea are mostly
mature ones. In sea shrimps are mostly confined to shallow coast
and do not occur beyond a depth of about 20 meters. The largest
sized prawn (P. monodon) is marine which reaches a length of 30 cms
and weight upto 150 gms. But is not very common. M. dobsoni, M.
monoceros, are most important specie to be cultured in India ,
Pakistan, Indonesia, Malaysia, Philippines and adjusted countries
P. monodon M. monoceros M. dobsoni
8. Commonly Cultured Marine Shrimp Penaeus merguiensis Banana
prawn Penaeus indicus Indian prawn Penaeus duorarum Atlantic pink
shrimp Penaeus aztecus Atlantic brown shrimp Penaeus setiferous
Atlantic white shrimp Penaeus monodon Black tiger prawn P.
merguiensis P. indicus. P. monodon P. duorarum P. aztecus P.
setiferous
9. 2. Estuaries Prawn The fauna of these regions is the same
except Parapenaeopsis stylifera which is exclusively marine. These
are mostly immature. The important areas of prawn production in
estuaries are the backwaters extending to the southern half of
Kerala coast. Several lakes like Pulicat, Ennur, Collair, Chilka,
etc and the mouth of numerious hill streams in the Malabar also
serve as fishing grounds for prawns. Besides this , the estuaries
of the Ganges and the Brahmaputra rivers in the east are of
considerable importance.
10. 3. Freshwater Prawn Macrobrachium sabriculs is a species
which is extensively a freshwater form. Metapenaeus monoceros and
Penaeus monodon are common in freshwater as well as salt water.
Macrobrachium carcinus and Macrobrachium malcolmsoni are fresh and
brakish water. For freshwater culture M. malcolmsoni is best
suited. M.sabriculs M. monoceros P. monodon M. carcinus M.
malcolmsoni
11. Reproduction The marine and brakish water specie spawn in
sea. They are drifted along with the current to coastal waters or
estuaries where they undergo development till they reaches the
jevenile stage. The post larvae feed upon the dead organic matter
of plants and animals and upon small benthomic organisms For
breeding the juvinile prawn has to enter the sea. The fresh water
specie like Macrobrachium malcolmsoni spawn in fresh water , then
they are drifted to estuaries and after attaining the juvenile
stage swim back to Fresh-water.
12. Penaeid Shrimp Life Cycle Shrimp have a maximum life span
of about 24 months.
13. Season for prawn fishery The ideal season for fishing at
Bombay coast is from August to October In Saurashtra it is from
July to Septmber. On eastern coast, it starts from moonsoon and
extend upto March-April. Fishing is done throughout the year in the
backwaters of Kerala. Different lakes have different fishing
season. In freshwater, it extends from March to June- July.
14. Nets for prawn The commonest type of net used on both the
coast is boat siene. The commonest type of net used on both the
coast is boat siene.
15. Life CycleNets for prawn In estuaries and backwaters, a
particular type of conical net, supported by a pair of stakes in
bieng used. This net has a wide mouth and is set against the tide.
The tidal water bring prawn and other crustaceans which get
engulfed into such nets. Other type of nets like cast net, drag
net, wall net etc are also used for this purpose. Small nets and
several other devices like trapping of prawn by clothes by making
small fences are bieng used in paddy fields which are also used for
this purpose. the crafts used for prawn fishing are the same as
that used for the collection of fishes.
16. Prawn Farming / Culture The purpose of prawn culture is to
convert ponds , tanks, paddy fields, estuaries and marine coastal
waters into productive places. There are two methods of prawn
farming. 1. Traditional Method 2. Intensive Farming
17. 1. Traditional Method It is old and conservative method.
This method is widely used in India. In this method the ponds
situated near estuaries and brakish water areas are selected. The
ponds remain connected with the outer main tidal stream by sluice
gates. A suitable environment for prawn development like depth,
salinity, nature of soil etc are created in advance. when the
incoming tide reaches a height of 50 cms above the pond level , the
sluice gates are opened and the shrimps are allowed to enter the
pond
18. Traditional Method A mesh screen is placed near the gate to
prevent the escape of the post larval stages of prawn at dead tidal
hours The developing shrimps depend entirely on natural diet.
However in Philippines where a slightly altered type of traditional
method is used and the natural diet has been largly suplimmented by
an artificial one. Collection and harvesting is generally done by
draining out the pond water in such a way as to prevent the escape
of prawns. Another method of harvesting is to set up a bag nets of
bamboo traps near the sluice gates. During the night electric bulbs
which atttract are also used for quick trapping.
19. 2. Intensive Method This method is extensively used in
Japan, includes not only the rearing of the post larval stages of
prawn but also its breeding and spawning at desired places by
providing the artificial environment. Dr. Fujinaga of Japan for the
first time in 1934, developed the process of artificial spawning of
prawns in localized areas. Matured males and females are released
in a small concrete tanks having an ideal environment for prawn
development. The temperature and oxygen concentration of the tank
is maintained artifically through aeration. Artificial
Aeration
21. Intensive Method After spawning the adults are removed in
order to save the possible destruction of eggs and hatching by
parents. The early larval stages are fed on phytoplanktons,
especially diatomes but when the larvae settled down on the bottom
and enter into the post larval stage they are provided worms, flesh
of fish etc as food. On attaining the considerable size, the larvae
are transferred to the production ponds. The production ponds have
two openings which inturn are connected to the main stream of water
through water pipes.with the help of hydraulic pumps the water in
the pond is made to circulate. The fixed mesh screens at the
outlets and inlets of the pond donot allow the shrimp to move out
of th pond.
22. Intensive Method After spawning the adults are removed in
order to save the possible destruction of eggs and hatching by
parents. The early larval stages are fed on phytoplanktons,
especially diatomes but when the larvae settled down on the bottom
and enter into the post larval stage they are provided worms, flesh
of fish etc as food. On attaining the considerable size, the larvae
are transferred to the production ponds. The production ponds have
two openings which inturn are connected to the main stream of water
through water pipes.with the help of hydraulic pumps the water in
the pond is made to circulate. The fixed mesh screens at the
outlets and inlets of the pond donot allow the shrimp to move out
of th pond.
23. Advantages of intensive Mathod This method gives much more
production than the traditional method. The U.S.A has an average
production of 3000 kg/ha of fresh water prawn per year. Japan has
fluctuating production of 2000 kg/ha. The flutuation depends on the
type and suitable conditions of the cultured ground. In India
intensive farming is in experimental stage.
24. Preservation and Processing Prawn is an important article
for export. As in case of fishes its meat detriorates very fast. So
for transportation of prawn to distanct places, they are processed.
Prawn is an important article for export. As in case of fishes its
meat detriorates very fast. So for transportation of prawn to
distanct places, they are processed.
25. For Short Distance If distance is short then they are
packed between layers of ice either entirely or after removing
caphalothrax.
26. Long time preservation For long time preservation generally
two methods are used: 1. Total drying 2. Semi-drying 3. Besides
these other methods like freezing, canning, smoking etc are also in
practicein different parts of India. Freezing
27. Total Drying Method In this method the entire prawn or
those with shells removed are dried in the sun for several days. In
some places, they are boiled in water before drying. The dried
materials are thrased to remove the shell. They are finally packed
in polythene bags for marketing.
28. Semidrying Technique This method is more popular because it
retain the flavour of the live specimen . In this method, the
prawns are boiled in the 6% brine for just 2 minutes. After that
the shell is removed and the prawns are dipped into saturated salt
solution for half an hour. The process is followed by drying in the
sun, but the drying is stopped beforethe flesh gets too hard. Such
semidried prawns (even after months) when soked in water give the
origional taste.