Effects of AquaMats(TM) on the growth of Nile tilapia (Oreochromis niloticus) fry in earthen ponds | |
| Author | Weerasooriya, Asha Chandani |
| Call Number | AIT Thesis no. AQ-01-23 |
| Subject(s) | Nile tilapia--Growth Ponds |
| 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-01-23 |
| Abstract | This study was conducted to assess effects of AquaMatsTM on the growth and yield performance of Nile tilapia (Oreochromis niloticus) fry, periphyton growth and water quality in earthen ponds at the Asian Institute of Technology during January to April 2001. There were four treatments with three replicates each: (A) non-feeding without AquaMats™; (B) non-feedinfu with AquaMats™; (C) feeding without AquaMats™ ; (D) feeding with AquaMats . The experiment was carried out in twelve 330-m2 ponds with a randomized complete block design. Sex-reversed all-male Nile tilapia fry of 1.58-1.73 g in size were stocked at 30.3 fish/m2 in all ponds, which were fertilized weekly with urea and triple super phosphate (TSP) at rates of 28 kg N and 7 kg P/ha/week. Fry in the two treatments with supplemental feeding were fed with commercial pelleted feed (AT feed, 35% crude protein, Cargill Siam Ltd.) at 30%, 6.5%, 6%, 4.4% and 4.2% body weight per day during the days 15-28, 29-42, 43-56, 57- 70, 71-90 after fish stocking. Feed ration was adjusted biweekly based on the feeding rate and fish standing crop, which was estimated using the sample weight, assuming 100% of survival rate. Growth performance in the feeding treatments was significantly higher than that in the non-feeding treatments (P < 0.05). In both feeding and non-feeding ponds, growth performance was not significantly different between the treatments with and without AquaMats™ (P > 0.05). However, there was no significant difference in yields between the treatments with and without AquamatsTM in non-feeding Eonds (P > 0.05), while yields were significantl~ higher in the treatment without AquamatsrM than that in the treatment with AquamatsT in feeding ponds (P < 0.05). AquaMats™ had no significant effect on water quality, in both feeding and non-feeding treatments (P > 0.05). Sixty-two periphyton species were identified on AquaMats™, and Bacillariophyta was the dominated genus with the largest number of species, followed by Chlorophyta, Cyanophyta, Euglenophyta and Xanthophyta. Towards the end of the experiment, total fouling solids increased, while periphyton biomass expressed as chlorophyll a concentrations on AquaMatsTM decreased drasticall;v.M which might be caused by the deposition of clay particles on the surface of AquaMats 1 due probably to the fish seining and tilapia grazing activity on pond bottoms. Compared to the treatments without A~uamats™, nutrients in pond sediments tended to lower in the treatments with Aquamats M' but without significant differences. The present experiment indicates that Aquamats TM did not enhance the growth and yield performance of Nile tilapia fry, promote periphyton growth, and improve water quality in earthen ponds. More researches are needed to assess the roles of Aquamats TM in Nile tilapia nursing ponds. |
| Year | 2001 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. AQ-01-23 |
| 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) | Lin, Chang Kwei;Yakupitiyage, Amararatne; |
| Scholarship Donor(s) | NORAD ; |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2001 |