Optimization of stocking rates of tiger shrimp under modified improved culture system

With the target of increasing the shrimp (Penaeus monodon) production through farm development and improved grow out management, an experiment was conducted with three different stocking densities viz. 5/m (T1), 7/m (T2) and 9/m (T3). Results of the experiment revealed that, among the water quality parameters, values of dissolved oxygen and transparency were lower in the higher stocking densities with significant difference (p<0.05) among the treatments. Other water quality parameters were similar in all the treatments. Bacterial load in bottom sediment had the trend to increase with increasing culture period and showed significant difference (p<0.05) among the treatments with the highest in the higher stocking density. Soil pH in the end sample reduced a little bit in all the treatments than the initial. Deposition of organic matter, phosphorus and nitrogen was related to the respective stocking densities. Final weight gain and survival rate of shrimp were significantly (p<0.05) higher in T1 than in T2 and T3. Stocking density of 5/m showed the highest production of 759.14±19.002 kg/ha, which was significantly (P<0.05) higher than that of 670.77±16.078 kg/ha obtained in T2, but similar to 701.24±33.507 kg/ha obtained in T3. The net economic return and BCR was also significantly higher (p<0.05) in the same stocking density (5/m) compared to others. Whereas, FCR value was significantly lower (p<0.05) in T1 than the other two treatments. However, pond ecological conditions were more congenial for shrimp culture in lower stocking density (5/m), which minimized the risk of disease outbreak in the respective stocking density, keeping the culture environment favorable.