Cultivation of black tiger shrimp, Penaeus monodon broodstock by reducing stocking density and transferring pond: Technical paper no. 14/1996

Black tiger shrimp, Penaeus monodon age of 4 months (23.64 g mean body weight) were cultured in earthen pond by reducing stocking density and transferring pond at National Institute of Coastal Aquaculture substation. Shrimp were stocked for 98 days in two ponds, 1,000 square m and 800 square m with the density of 3.1 ind/square m and 7.2 ind/square m respectively. After harvesting, the survival rate were 62.89 percent and 29.79 percent with mean body weight of 56.0 g. Result revealed lower stocking density gave 50 percent greater survival rate than the higher density. These two stocks were then mixed and transferred to 3,200 square m pond at density of 1.14 ind/square m. After 80 days of cultivation, the survival rate was 70.99 percent with average body weight of 89.97 g. Shrimp were then restocked at 0.81 ind/square m for 70 days in another pond with the same area. Upon harvesting, survival rate was 61.71 percent with average body weight of 106.19 g. Throughout the total culture period (248 days), the survival was 18.10 percent with mean body weight gain (BW) of 83.27 g or 0.33 g/day. This final size of 106.19 g BW was comparable to those of wild broodstock, 51.85 percent of female were mated and 41.67 percent of female with full white terminal ampullae. Harvested shrimp were transferred to landbased concrete tank for induced maturation experiment. Ovarian development was enhanced and 4,123,500 eggs were laid. Nauplii were hatched with the hatching rate of 21.75 percent. From this study, shrimp 4 month old at the size of 40 to 50 ind/kg can grow up to be broodstock in earthen pond within one year under gradual reduction of stocking density from 3.1, 1.1 and 0.8 ind/square m and transferring pond. Further study is being plannned for shortening culture period, more suitable stocking density and feed. Cost (not included pond construction, salary and equipment maintenance) of black tiger shrimp broodstock from this study was 146.81 baht.