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

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for chemical and microbiological analysis offers free water quality
analysis or disease diagnosis. The extension centres conduct seminars
and training courses. A large nuber of processing plants capable of
producing value added products have been set up. Most important of all
is the availability of cheap and skilled work force.
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Although juveniles of 12 species are recorded in the catch of
the Singapore ponds (Hall, 1962), S species, namely B. indicus, B.
meprgsuirensis, Metgapenaeus ensis, Q. pburkenroapdi and Q. pbfireuvicornis
contribute to major portions of the catches. The method of shrimp
culture as practised is that of rearing young penaeid shrimps brought
in with every incoming tide. The catch in these ponds ranges upto 800
kg/ha/year.
Bangladesh
hi Bangladesh, abundant land, water and seed stock allow to
produce shrimp at very low cost. They polyculture shrimp and fish in
the pond after the rainy season when the creeks becoe brackish. In
other areas of salt ponds, shrimp and fish are produced, once the rain
beginsso that salinities fall.
Farmers rely on tidal flows for filling and draining their
ponds. Pumps are not used. The entrance of predator and competitor
fish with the inflow of water at high tide is prevented by the careful
use of sluice gate screens.
Farmers construct nursery impoundments within the larger ponds.
Along with the arrival of most seed stock with the incoming tide,
farmers stock at low rates of 10,000 to 30,000 fry/ha. Most farmers do
not provide supplemental feed. Hence, the production worked out to
only 250 kg/ha.