Development of pond culture of Thai Nile tilapia (Oreochromis niloticus L.) and its marketability in Hanoi, Vietnam | |
| Author | Cao Thang Binh |
| Call Number | AIT Diss. no. AS-98-02 |
| Subject(s) | Nile tilapia--Vietnam--Hanoi Pond aquaculture--Vietnam--Hanoi |
| Note | A dissertation submitted in partial fulfillment of the requirements for the degree of Doctoral of Technical Science, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Abstract | The dissertation consists of two parts: designed experiments and market surveys. A series of three experiments and three surveys were conducted for development of tilapia culture in North Vietnam. The experiments focused on development of low cost supplemental diets using locally available ingredients, economically optimal combinations between feeding and fertilization, and overwintering methods for Nile tilapia culture. The surveys concentrated on marketing aspects, including in-depth investigations on consumer behavior, fish marketing channels, and fish farming practices. Findings show that the diet containing 20% crude protein formulated from concentrated chicken feed (40% crude protein) and cassava meal gave the best fish growth and economic returns, with daily weight gain of 1.91% g/fish, production of 4.17 kg/m3, FCR of 1.64, and gross margin of US$ 0.35/kg of produced fish. Application of this diet at 50% of normal feeding rate (NFR) in fertilized ponds was the most economically vaible and environmentally friendly as it reduced the feed conversion ratio (FCR) by 42% and increased the gross margin by 30%. As tilapia culture suffers from low temperature in North Vietnam, increasing pond water depth to 2.0 m or using artificially sheltered ponds at 1-m depth were feasible for overwintering the fish. Holding facilities (i.e. cages and earthen ponds) were found not to significantly affect survival of the overwintered Nile tilapia (P> 0.05). Findings from the marketing studies show that a majority of the respondents liked eating fish and ate them very often. Fish was the second most popular source of animal protein in their daily meal, ranked after pork. In choosing foods, people mainly considered personal preference and ability to cook various dishes. Common carp, large tilapia, and grass carp were ranked as the three favorite and also the most consumed species. When tilapia is purchased, people mainly considered freshness (live fish) and fish size (equal to or greater than 200 g). Fish marketing channel in Hanoi was short and simple with the dominance of middlemen. Total marketing cost per kilogram of fish averaged VND 533 (US$ 0.04), of which transportation constituted 32.3%, taxes 42.7%, and miscellaneous costs 25%. Marketing margin ranged from VND 1,500 to VND 3500/kg, depending on species, freshness, and size. The main factors determining fish price were species, size, form, and marketing period (summer or winter). Three main farming models were found in the study area. namely polyculture of carps without tilapia, carps with Vietnamese tilapia strains, and carps with newly introduced Thai Nile tilapia. Stocking density in these systems ranged from 2.0 to 3.9 fish/m2. Municipal wastewater, pig manure, night soil, brewery wastes, and on-farm grasses and vegetables were currently the most common pond inputs. Fish production was found to have a significant positive correlation with stocking densities of Indian carp and Thai Nile tilapia, and feeding rate of brewery wastes but negatively correlated with application rate of night soils (P<0.05). The integration of Thai Nile tilapia in carp polyculture systems has increased both fish production and economic returns substantially. Thai Nile tilapia would have excellent market potential in Hanoi since a majority of consumers and fish traders rated it highly in terms of size at harvest, meal texture and taste, and overall appearance. Most farmers who have cultured Thai Nile tilapia also rate it superior to current Vietnamese tilapia. However, most fish farmers were currently facing constraints of inadequate capital, market and marketing problems, fish diseases, and unavailability of high quality seeds. |
| Year | 1998 |
| Type | Dissertation |
| School | School of Environment, Resources, and Development |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Agricultural and Aquatic Systems(AS) |
| Chairperson(s) | Lin, Chang Kwei; |
| Examination Committee(s) | Demaine, Harvey;Little, David J.;Speece, Mark W.;Diana, James S.; |
| Scholarship Donor(s) | DANIDA;Asian Institute of Technology, Aquaculture Outreach Programme;USAID (CRSP, Pond Dynamics/Aquaculture); |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 1998 |