Culture for Tiger Shrimp
In order to develop location-specific culture technologies for shrimp and to demonstrate its techno-economic feasibility, tiger shrimp Penaeus monodon culture was taken up in a brackishwater farm at Danti - Umbharat Centre of the Navsari Agricultural University, Gujarat. The farm comprising four ponds of 0.16 ha each, has two reservoir ponds (0.14 ha each), one Effluent Treatment Pond (0.03 ha), five stage filtration of intake water, bird fencing, crab fencing and dog fencing to ensure biosecurity. Standard pond preparations protocols were followed and P. monodon seed (PL 30 & PL 40) from the CIBA hatchery were stocked @ 8.3 nos./sq m in three ponds on 4th June 2009, following the standard acclimatization procedure. However, due to the prevailing higher salinity in the pond at the time of stocking (40 ppt), the survival rate was poor. The shrimp were fed with ‘Bismi feed’ developed and commercialized by the Institute @ 10% of body weight initially and gradually reduced to 1.68 % at the end of culture. During the culture, agricultural lime and dolomite were applied during low pH conditions; to reduce pH, NH3 and H2S concentrations, fermented rice juice and zeolite were used whenever needed in all the ponds. Immunostimulant (CIBASTIM) was mixed with feed and fed to shrimp on a weekly
basis in ponds 2 and 3 whereas pond 1 served as a control. During the culture and after each pond treatment, water samples were analyzed for pH, salinity, CO3 and HCO3 alkalinity, Ca+Mg hardness, total N and phosphate. There was not much difference between the ponds with respect to water parameters. The discharge water from the ponds during the culture was taken to the ETP and then used for raising Salicornia crop in the adjacent plot.
Harvesting of shrimps was done after 122 days of culture and the results of production and survival . Though the survival rate was poor in all the ponds due to high salinity at the time of stocking, the survival rate was comparatively higher in CIBASTIM treated ponds. The overall survival rate was 47.1%. The production and quantity of grade A shrimp was also higher in ponds 2 and 3, compared to control by 9% and 19%, respectively. Though quantity of grade B was less in treated ponds than control, the overall production was higher by 6.6% and 11.5% in ponds 2 and 3, respectively compared to control. The total production obtained was 551kg and the productivity was 1147.9 kg/ha/4 months. A revenue of Rs.1,78,956 was realized from this culture. The results indicated that with biosecured aquaculture and by using CIBASTIM, production of healthy shrimp can be achieved with the possibility of using the discharge water to raise Salicornia crop as an additional source of income.