Effects of stocking densities on grow performance and survival rate of black tiger shrimp (Penaeus monodon) postlarvae applying bioflocs technology

Abstract

Effects of stocking densities on growth performance and survival of black tiger shrimp ( Penaeus monodon ) post-larvae applying bioflocs technology was studied in order to contribute to practicial production in the region. A triplicate experiment was randomly designed with five treatments of stocking densities at 200, 400, 600, 800 and 1000 PL/m3 in 0.5-m3 composite tanks with water salinity of 15‰. Shrimp postlarvae with initial body length and weight of 13.4mm and 0.01g were used for the experiment. Shrimp were fed daily with pellet feed and wheat flour was used as carbohydrate source to create and maintain Biofloc at C:N ratio of 10:1. During rearing period,water quality parameters such as temperature, pH, alkalinity, TAN, and nitrite were recorded showing suitable range for shrimps. After 30 days of rearing, survival rates of shrimps stocked at 200 PL/m3 and 400 PL/m3 (96.6% and 97.1% respectively) were significantly higher than those of the other treatments. However, productivity of postlarvae in treatment of 400 PL/m3 (389 PL/m3) was significantly higher than that of the treatment 200 PL/m3 (196 PL/m3). Shrimp body weight and length after 30 days of rearing were not significantly different among the treatments. The findings of the experiment therefore recommended stocking density of 400 PL/m3 for nursing of black tiger shrimp post-larvae under under bio-floc systems.