studies on improved practices of prawn farming for higher ...

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They are traditional extensive with improved practices, scientific
extensive and semi-intensive farming. Results have been achieved upto
4-8.5 tonnes/ha/crop in a few places of Tamil Nadu, Andhra Pradesh and
Maharashtra (Anon, 1990 G 1992). The success has been attributed to
the adoption of better management techniques such as high stocking
density of healthy fry, 30% daily water exchange, paddle wheel aeration
and use of high energy imported feed.
Increased production can be attained through intensive culture.
Where sites are abundantly available, the increase can be achieved
through area expansion. Either existing farms can be converted as
semi-extensive or new areas can be developed.
In any case, the development is implemented using appropriate
engineering designs aimed at
a) reducing size of the farm area to small manageable sizes
b) providing facilities for effective water control and
circulation and c) perhaps excavation and levelling of the ponds to
attain appropriate depths required in the culture.
Ecuador is making the transition from extensive to semiextensive
farming. China also pursues sani-intensive farming. Saniintensive
farming practices are becoming popular all. over the world.
Ifltsnsiveiermina
Intensive farming is characterised by small ponds (upto 0.5
ha), high stocking densities (more than 2 lakhs juveniles/ha), heavy
feeding, waste removal, aeration and round the clock management. There
is complete control over water management in quantity and essential
qualities. The water exchange required is above 30% per day. Aeration
using aerators and feeding with high quality feeds have to be resorted.
The metabolites have to be reoved periodically through central drain.
Water qua].ity has to be maintained very carefully to avoid diseases.