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

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in ponds in association with Chanos chanos from olden times. But as on
today monoculture is preferred. Unlike the culture of_B. japonicus in
Japan, the culture of B. monodon in the Philippines is dependent on
natural supply of seed or fry.
As a result of the demand, the collection of the fry has
developed into a distinct and lucrative fishery. Farmers used lower
stocking densities with supplemental fresh feeds (like molluscs and
trash fish) and high quality_§. monodon fry.
Recently with the advent of backyard hatcheries, artificially
produced fry are profusely used for intensive shrimp culture.
Many discontinued the IMHB of chemicals (disinfectants,
algicides and antibiotics) in order to lower disease out break caused
by Monodon baculovirus (MBV) etc.
85% of the industries‘ feed requiranent amounting to 1 lakh
tonne/year is produced by 21 shrimp feed mills. Feed accounted for 60­
70% of production costs.
Philippines and Indonesia both had pollution problems due to
intensive shrimp farming forcing the farmers to retreat to semiintensive
culture. Nevertheless, intensive farms increased effluent
load on the rivers.
Vietnam
iShrimp production/ha in Vietnam is the lowest by international
standards as lnost farmers relied only" on the seed stock; that: was
brought in by the incoing tide. Also poor water exchange and lack of
eradication of pests contributed to the low production of 188 kg/ha.