Effects of adding shrimp (Penaeus monodon) into intensive culture ponds of Nile tilapia (Oreochromis niloticus) at different densities | |
| Author | Pham Cu Thien |
| Call Number | AIT Thesis no.AQ-03-38 |
| Subject(s) | Nile tilapia Shrimp culture |
| 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-03-38 |
| Abstract | The study was conducted at the Asian Institute of Technology (AIT), Thailand for 133 days from 21 May to 2 October 2003. The experiment was to investigate effects of adding shrimp (Penaeus monodon) to Nile tilapia ( Oreochromis niloticus) ponds on the growth performance, water quality and nutrient utilization efficiency in different stocking combinations of tilapia-shrimp polyculture. Nine 200-m2 earthen ponds (20 m x 10 m x 1 m) were used for the experiment. There were three treatments in triplicate each: Nile tilapia at 1/m2 and shrimp at l 5/m2 (low tilapia density), Nile tilapia at 2/m2 and shrimp at 15/m2 (medium tilapia density), Nile tilapia at 4/m2 and shrimp at 15/m2 (high tilapia density). The treatments were randomly allocated to the experimental ponds. Final mean weight and mean daily weight gains of Nile tilapia in the low tilapia density treatment was significantly larger than those in the medium and high tilapia density treatments (P<0.05), between which there was no significant difference (P>0.05). However, total weight, total weight gain, net and gross yields were highest in the high tilapia density treatment, intermediate in the medium tilapia density treatment, and lowest in the low tilapia density treatment (P<0.05). Feed conversion ratio was significantly higher in the high tilapia density treatment than those in the low and medium tilapia density treatments (P<0.05), between which there was no significant difference (P>0.05). Growth of shrimps was fast in the first 28 days when they were fed with pelleted shrimp feed, however, shrimp growth slowed down in the remaining culture period after feeding stopped. Final mean weight was not significantly different among all treatments (P>0.05), however, other growth parameters of shrimp including total weight, survival rate, gross and net yields in the high tilapia density treatment were significantly poorer than those in the medium and low tilapia density treatments (P<0.05), between which there were no significant differences (P>0.05). Nutrients incorporated by Nile tilapia biomass accounted for 48.01 %, 52.89%, and 48.99% of TN, and 60.55%, 68.47% and 62.25% of TP inputted from fertilizer and pelleted feeds in the low, medium and high tilapia density treatments, respectively, while shrimp recovered only 1.10% and 0.33% of TN, and 0.55% and 0.27% of TP in the low and medium tilapia density treatments. However, nutrients lost through dead shrimp in the high tilapia density treatment. Overall mean DO concentrations at both surface and bottom were highest in the low tilapia density treatment, intermediate in the medium tilapia density treatment, and lowest in the high tilapia density treatment (P<0.05). For TAN, overall mean concentrations of TAN was lowest in the low tilapia density treatment, intermediate in the medium and highest in the high tilapia density treatments (P < 0.05). All treatments gave negative net returns. However, the highest loss was in the high tilapia density treatment, followed by the medium tilapia density treatment, and the low tilapia density, due to the loss of shrimp and consumption of costly feed by Nile tilapia. The experiment has showed that the addition of shrimps into Nile tilapia ponds is feasible, however, not attractive economically in the present experiment. More research is needed to optimize the stocking density of both Nile tilapia and shrimp, and fine-tune feeding regimes. |
| Year | 2003 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. AQ-03-38 |
| 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) | Yi, Yang; |
| Examination Committee(s) | Yakupitiyage, Amararatne ;Somsak Boromthanarat ;Fitzsimmons, Kevin; |
| Scholarship Donor(s) | SIDA;PD-A CRSP;Asian Institute of Technology |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2003 |