A thesis Submitted in partial fulfilment of the requirements £or the degree of Master o f Science, School of Environment, Resources and Development

Thesis (M.Sc.) - Asian Institute of Technology, 1989

An assessment of the use of rice bran as a fish feed was carried out in four areas in Udon Thani province of the North east Thailand, representi11g four agro-ecological zones in the region. The study included a survey of fisl1 farming population in The selected areas to assess t.li e use of rice bran as a fish feed; evaluation of rice .bran samples collected from the field in terms o f the quality; a storage study to evaluate l be quality changes of rice bran on storage and a case study of two villages to study The dynamics of rice bran marketing in the villages. Average area of a fish pond was found to be 1 .16 ha , yielding on an average 1 5 O O Kg/ha of which 20 . 1 per cent was us e d for home consumption. The survey confirmed The earlier observation s l hat rice bran was the most commonly used fish feed being used by 65 % of the fanners. Farmer ' s awareness of the locally available feed stuffs was a1so observed. The common fish pond inputs were vegetables, termites, duck weed, ipomea and cassava leaf. Differences in fish pond inputs used , reflected local availability and agricultural practices of Ll1e area. 77 % of the farmers were found to use less than 1 Kg of rice bran and 44 % of the farmers were found to feed rice bran once every day. Limited availability of rice bran was reported to be the reason for confining the use of rice bran . The low fish yie1d is attributed to the low usage of feed inputs of which rice bran is a major constituent. A clear difference in the proximate composition was observed between the rough, smooth and mixed rice bran available to the farmers. A rapid increase in free fatly acid was observed on storage, indicating development of rancidity which was a major reason restricting the storage of rice bran . Case study of marketing of rice bran revealed that the existing marketing system, was geared to the needs of the village , but the pig and the duck subsystems were found l o be the major consumers of rice bran, leaving the fish subsystems at a disadvantage Seasonal differences in price and availabi1ity was observed depending on the farming activities ln the village.