A comparative study of traditional and improved traditional culture system of black tiger shrimp (Penaeus monodon) in Khulna, Bangladesh

A comparative study of bio-economic feasibility of black tiger shrimp (Penaeus monodon) was carried out in Dacope and Paikgacha Upazila of Khulna district, Bangladesh. A total of six Ghers (a special type of agricultural field with raised high surrounding banks/borders situated by the side of a river) from different locations of the greater Khulna district were selected as study area. The study observed the following attributes: growth, growth rate (GR), survival rate (SR), production, production rate (PR), production cost (PC), net profit (NP), gross profit (GP), and ratio of profit (RP) to total cost (TC). The size of the ponds in T and IT culture systems varied in size from 15 to 39 acres respectively. No nursing practice was observed either in T or in IT ponds. Nevertheless, fertilizers and supplementary feeds were used in the IT culture system as post-stocking management. The pond dike system was found to be stronger in IT ponds than in T ponds. No apparent variations of water quality parameters were observed in T and IT ponds throughout the culture period. The average growth rate of shrimp was higher in T ponds than that of IT ponds while the average survival rate was found to be higher in IT ponds than T ponds. Additionally, the average PR, PC, GP and NP was higher in IT ponds compared to T ponds. Moreover, RP to TC per kg of shrimp in T and IT ponds was higher in IT ponds compared with T ponds. This study found that IT culture system was more economical and profitable than that of the T culture system in terms of NP, GP and RP to TC. However, GR was higher in the T culture system than the IT culture system, which is attributed to the lowerstocking of post-larval shrimp in T ponds