Abstract:
The objectives of writing this thesis are to study the factors, stages, costs, general characteristics, and problems related to the backyard hatchery operations of the giant freshwater prawn (macrobra-chium rosenbergii). The data used in this study were obtained partially through personal interviews with four hatchery owners selected from the Cha-Choengsao Province, and partially from official records of relevant government agencies as well as private sources. The findings from this study are as follow. The production of juvenile prawns from the backyard hatcheries fluctuates greatly during the year due to water shortages and output variabilities. Various sizes and types of ponds, wells, and tanks for storing waters; equipment, gravid female prawn, feeds, and labor (household as well as hired) were the main input factors of hatchery operation. A larger proportion of investment went to the ponds, wells, and tanks. Brine shrimp (artemia salina) consisted of 56.45 per cent of total production costs. Production cost per unit of juvenile prawn was 0.1532 baht. The components of this cost were raw materials (0.0971 baht), labor (0.0279 baht), and production overheads (0.0282 baht). The cost analysis revealed that unit production cost of juvenile prawns was related to the total production costs and output quantity. The unit production cost would decrease if the decrease in the rate of total production costs is greater than the decrease in the rate of output quantity, or the output quantity increases or remains unchanged with the decreasing rate of total production costs, or the rate of total production costs increases less than the rate of output quantity increase. A number of important problems related to the hatchery operation were also discovered from this study. In addition to shortages of quantity as well as quality of water, the hatchery owners also frequently faced the problem of shortages of gravid female prawn for brooding, low survival rate of the juvenile prawn, disequilibrium of demand and supply conditions, and the highly perishable nature of the juvenile prawns which resulted in the sellers being at the mercy of the market conditions. Some practical recommendations are offered based on the research findings. Firstly, the hatchery owners should explore the means to increase their knowledge regarding production and marketing. Secondly, the prospect of establishing a hatchery owners co-operative to facilitate co-operations among the members in pricing, marketing and information exchanges should be seriously explored. Thirdly, the relevant government agencies should take a greater role in promoting the hatchery industry by giving more subsidies in the form of low-interest loans or credits both short or long term, extension services, and publicity services.