Comparison between the open system with water exchange and closed system with aeration for intensive culture of giant freshwater prawn (Macrobrachium rosenbergii) | |
| Author | Quaiyyum, Md. Abdul |
| Call Number | AIT Thesis no.AQ-04-22 |
| Subject(s) | Shrimps--Effect of water quality on Water--Aeration |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. AQ-04-22 |
| Abstract | An experiment was conducted for intensive culture of giant freshwater prawn, Macrobrachium rosenber~ii in an open system with water exchange and closed system with aeration in six 5-m outdoor cement tanks with earthen bottom at the Asian Institute of Technology (AIT) for 128 days. The objectives of this experiment were to compare growth and production performance of prawns, assess water quality, and evaluate nutrient utilization efficiency and economic performance between the open system and closed system. The two culture systems were considered as treatments with three replicates each. The tanks were fertilized twice with urea and triple superphosphate (TSP) at rates of 28 kg N and 7 kg P/ha/week prior to stocking prawns. Prawn juveniles with an average weight of 2.8 g were stocked at 19 prawns/m2 . Commercial pelleted feeds with 40% crude protein (small size) and 32% crude protein (medium size) were given ad libitum daily at 0730-0830 h and 1600-1700 h. Smallsize feed was used during the first 30 days, and medium-size feed was used during the rest of culture period. All tanks for the closed system were provided with continuous aeration ( 4 air stones/tank), while water was exchanged weekly at 10%-30% in the tanks in the open system. There were no significant differences in mean weight at harvest, mean weight gain, daily weight gain and specific growth rate of prawns between the open system with water exchange and closed system with aeration (P<0.05). Survival in the closed system with aeration (88.52%) was significantly higher than that (40.71 %) in the open system with water exchange. Gross and net yields were 10,950.0 and 9,446.8 kg/ha/year, respectively, in the closed system with aeration, which were significantly higher than those (5,902.7 and 4,375.4 kg/ha/year) in the open system with water exchange. FCR was 1.94 in the closed system with aeration, which was significantly lower than that (3.54) in the open system with water exchange (P<0.05). Overall mean and final values of most water quality parameters were not significantly different between the two systems (P>0.05). Average nutrient recovery percentages by prawns were 12.19% TN and 8.02% TP in the open system, which was significantly lower than that (27.25% TN and 15.73% TP) in the closed system (P<0.05). Average percentages of wasted nutrients were 87.81 % TN and 91.98% TP in the open system, and 72.75% TN and 84.27% TP in the closed system. Average nutrient requirements to produce 1 kg of prawns were 164.6 g N and 33.0 g P in the open system, and 95.6 g N and 19.0 g Pin the closed system. On average, 26,298 Land 3,223 L of water were used for producing of 1 kg prawn in the open system and the closed system, respectively. Negative net return was obtained in the open system, while positive net return was achieved in the closed system. The present study demonstrated that the closed system with aeration is more suitable for intensive prawn culture, and is feasible technically, profitable economically and environmentally more friendly. |
| Year | 2004 |
| Corresponding Series Added Entry | Asian Institute of Technology.--Thesis ;--no. AQ-04-22 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Aquaculture and Aquatic Resources Management (AQ) |
| Chairperson(s) | Yang Yi.; |
| Examination Committee(s) | Amararatne Yakupitiyage;Bart, Amrit N.; |
| Scholarship Donor(s) | Royal Danish Embassy Dhaka, Bangladesh.; |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2004 |