Freshwater Farming of Brackish Water Shrimp, Penaeus monodon (Fabricius) witli Indigenous Technologies in Purba Medinipur District of West Bengal, India

摘要

Brackisiiwaterslirimp(Penaeus monodon) farming expanded rapidly after the technical viability of this culture system was established and farmers discovered that the high profits derived from shrimp production could easily offset increased costs associated with this culture. These factors facilitate the spread of brackish water shrimp farming into fresh-w'ater agricultural areas of Purba Medinipore District of West Bengal that never experience salt water intrusion. The emergence of brackish water shrimp farming within paddy growing regions of Purba Medinipore District has raised concerns regarding potential environmental impacts and the suitability of conducting this activity within highly productive freshwater agricultural areas. In the present study an attempt had been made to farm the black tiger shrimp. Penaeus monoclon in freshwater condition with innovative technologies. The PCR tested P. monodon seeds (PL^,,) were stocked in all freshw'ater earthen tanks after proper acclimatization @ 24,000nos/tank. The average salinity of the tanks were recorded be-tween 0.0063 ppt to 0.04 ppt throughout the culture period. The shrimps w'ere fed with branded feed and the feeding schedule was based on check-tray method as w’ell as a feed chart developed by the scientists. A home-made probiotic juice prepared from the mixture of molasses, yeast, paddy flour and water was used biweekly @ 1—2 ppm to maintain a healthy environment in the tank as this was a zero water exchange culture system. Shrimps were cultured until they attained 30 g in each tank. After final harvest, the survival rates were almost 15% and 79% respectively and the FCR were ranging between 1.61 to 1.66.