This document provides an overview of freshwater prawn farming. It discusses the introduction and classification of common freshwater prawn species used in farming. The life cycle, farming strategies, hatchery and pond management, water quality, feeding, growth, harvesting, and yields are described. Extensive, semi-intensive and intensive farming methods are compared. Advantages include providing nutrition and reducing health risks, while disadvantages include reliance on rainwater and inadequate commercial feeds.
2. Content:-
INTRODUCTION:-
Fresh water prawns:-
Classification:-
Composition:-
Identification:-
Life cycle:-
Farming strategy:-
Prawns hatchery/hatched tank management:-
Ponds construction:-
Water quality:-
Food and feeding habits:-
Growth to maturity:-
Harvesting:-
Yield:-
Advantages:-
Disadvantages:-
3. INTRODUCTION:-
Fresh water prawn farming has emerged since early 1960 in world in india 1990.
marine shrimp are grown in earthen ponds located in coastal areas of countries
with tropical and subtropical climates.
The fresh water prawns attains a good size in relative less time .
Fresh water prawns commonly inhibits the indian lakes ,reservoirs,ponds and low
salinity areas .
prawns farming quickly expanding areas.
4. Fresh water species:-
Fresh water prawns of the genus Macbarachium are very suitable for intensive
culture .
The main species of Macrobrachium are as -:
Macrobrachium rosenbergii
Macrobrachium malcomsonii
Macrobrachium rude
Macrobrachium idae
5. Classification of fresh water prawns macrobrachium
rosenbergii:-
Kingdom : Animali
Class : Malacostraca
Order : Decapod
Family : Palaemonidae
Species : rosenbergiii
9. Farming
Strategies:-
extensive :-
-large ponds
-low stocking densities
-little management or investment
semi-intensive:-
-falls in between the two extreme of intensive and extensive .
Intensive:-
-smaller ponds
-aeration
-high stocking densities
-feeding
10. Prawns hatchery/hatched tanks
management:-
The hatchery building is usually associated with the nursery tank and grow out
ponds in terms of water supply and other requirements .
A fresh water prawns hatchery produces PL for growing out ponds and for sale to
other prawn grow out enterprises .
Berried female ready for spawing should not be disturbed and should be kept
secluded in the hatched .
Start with 500 L fresh water in a 1000 L hatched tank , and stock a maximum of 3-4
berried female.
Keep the temperature at 25˚c - 30˚ c and pH 7.0 - 7.3 untill the eggs hatced .
Tanks water should be kept clean and free of dirt and debris through regular water
changes and bottom – siphoning .
12. Water
Quality:-
fresh water a river ,streams or lake ,rainwater ,or ground water can be used.
Hardness (AS CACO3)should be in the range 50-100 ppm.
Seawater is disinfected with 10ppm of calcium hypochlorite and stored for at least
a week before use.
Water quality for grow out ponds:-
Temperature : >68F
Salinity : 0.5-35ppt
Dissolved oxygen : >5ppm
pH : 7.0-8.3
Unionized Ammonia : <0.01ppm
Nitrite : <1.0ppm
Nitrate : <60ppm
13. Food and Feeding
Habits:-
The larvae are carnivorous and in culture they are fed on live ,newly hatched bring
shrimp.
Isochrysis:-
-brown algae
-(3-5ưm)
Chaetocereos:-
-Diatom
- (4-6ưm)
Tetraselmis:-
-green algae
-(10-15ưm)
Juvenile and adults prawns are omnivorous.
They feed on a wide variety of food items such as aquatic worms ,insects ,flesh and
offal of fish and other animals,grains,nuts,seeds,fruits,algae,tender leaves and
stems of aquatic plants.
In the culture medium artificial artificial feed also use for food of prawn .
14. Growth to maturity:-
The post larva grow to maturity within 4-7 months in fresh water ponds.
The PL grow to maturity is depending on temperature ,food and environmental
conditions.
The maturity stages of females and male can be determined by external
examination of the overy , and testis.
15. Harvesting
:-
Crops are normally ready for harvesting in 90 – 120 days .
Ponds are sometimes partially harvested using traps or seine nets .
Normally prawns are 25 – 35 gm each .
Prawns are washed , graded and generally cooked before marketing .
Some prawns are sold green and others are individually quick – frozen for storage
and sale at a later date .
17. Adventages:-
Help to prevent hair loss.
Helps maintain healthy bones.
Helps improve memory performance .
Gives relief from menstrul cramps in women .
Beneficial in eliminating bad cholesterol .
Reduces risk of lungs and prostate cancer.
18. Disadventages
:-
Culture mostly dependent on rain water; no assured perennial water supply or
drainage network.
Available commercial feeds are either inadequate quality or are too expensive .
Poor nursery practices .
