1Aquatic Animal Health Research Institute
Department of Fisheries
Kasetsart University Campus
Jatujak, Bangkok 10900, Thailand
2National Institute for Coastal Aquaculture
Kaoseng, Songkhla, Thailand
Chinabut, S., T. Somsiri and Y. Danayadol. 2002. Impacts of disease in small-scale aquaculture in Thailand: case studies. p. 81-84. In: J.R. Arthur, M.J. Phillips, R.P. Subasinghe, M.B. Reantaso and I.H. MacRae. (eds.) Primary Aquatic Animal Health Care in Rural, Small-scale, Aquaculture Development. FAO Fish. Tech. Pap. No. 406.
Small-scale aquaculture is an important activity in Thailand, particularly for low-income people throughout the country. People culture fish as a low-cost protein source and for family income. Although it has been recognised that disease has an impact on aquaculture, the extent of this impact on small-scale aquaculture is not well documented. Here, the socio-economic impact of disease on small-scale freshwater aquaculture in northeast, central and southern Thailand was studied using questionnaires. A total of 74 farmers from nine provinces were interviewed. The species cultured were ornamental fishes, such as angelfish, goldfish and guppies, and foodfishes such as catfish, snakehead, carp and tilapia. Frog and soft-shell turtle culture was also included, as culture of these animals has increased rapidly over the past three years to become a major source of household income. It was found that disease problems had an impact by reducing production, which, in turn, caused a decline in income and increased debt. Flooding was also one of the major problems causing serious losses.
Fish as a source of protein for low-income groups in Thailand normally comes from small-scale aquaculture production or fisheries. The impact of health problems in small-scale aquaculture is recognised, however, there are few published documents or statistics to indicate the extent of this problem. Therefore, a questionnaire survey to gather such information was conducted. This paper presents the results of analysis of these data from small-scale freshwater aquaculture in Thailand.
Sampling sites were selected to cover small-scale freshwater aquaculture throughout the country. A total of 74 farms from nine provinces were sampled. The farms were divided into three groups: grow-out ponds or cages, fingerling production and hatcheries. Among these farms, the operation could involve monoculture, polyculture, integrated farming or polyculture with integrated farming. The species of aquatic animals cultured included hybrid catfish, snakehead, climbing perch, gourami, carps, tilapia, sea bass, giant freshwater prawn, frogs, soft-shell turtles and ornamental fishes.
The income of the farmers can be divided into three groups as shown in Table 1. The average income per person was US$874. Using the figure of 1 US$/day as the poverty line, 34 out of 74 samples were below an annual per capita income of US$365/yr. All members of this group were involved in fish culture. The better off individuals tended to be involved in ornamental fish culture, or turtle/frog culture.
Farmers were growing fish as a source of income and food, some were growing fish as a hobby or for status, others to supplement income from growing rice, working in the city, or growing fruit, vegetables or livestock.
Table 1. Groups of small-scale farmers divided by income.
Most of the farmers have experience or have been involved in aquaculture for around four years. The wife and children spend more time looking after the fish than does the husband.
Initially, farmers coming into aquaculture will try to learn how to grow fish by themselves. Later, they may get more information from their neighbours, friends or other farmers. The government is involved in transfer of knowledge about aquaculture through the organisation of training courses or workshops once or twice each year.
The major problem for small-scale aquaculture in Thailand is related to the amount of water supply. Flooding is an uncontrollable problem that causes serious loss in aquaculture. Farmers rank disease second as a problem, along with various other problems.
Around 65% of the farmers surveyed thought that aquaculture, especially small-scale aquaculture, was profitable. Fifty-seven percent of the farmers ranked disease as an important issue in aquaculture. Less than 50% of the farmers thought that aquaculture was a risky business. Some of the farmers indicated that having a fishpond gave them high status in the community.
Information from the group that earned less than US$365/capita/year, is slightly different from the overall data. Fifty-nine percent of the farmers in this group thought that aquaculture is profitable. However, 49% of farmers still recognise that disease is an important issue.
Normally, farmers can choose fry for stocking. However, during the peak season for stocking fish, they may have to take whatever is available because of the higher demand. Most of the farmers cannot tell the difference between healthy and unhealthy fry.
In general, farmers can recognise sickness in the fish on their farms. Partial mortality and abnormal behaviour are the most common signs of sickness. Sickness normally occurs during the rainy and cold season, with some farmers facing problems just before harvesting. In this case, it will cause more financial loss due to feeding costs.
Disease problems will reduce the household income because the market price of the fish will decline. An indirect effect of disease in aquaculture is increased family debt. After experiencing disease, there is a strong desire among farmers to change the species cultured. Some farmers may stop promoting the business, however, none of them thought about ceasing to practice aquaculture.
Economic loss due to disease was reported as 38%. Low-income groups (<$365/capita/yr) were also affected by disease problems; of the eight farms within this group that reported losses due to disease, the average loss was US$148, or around 64% of the reported average household income.
Most farmers will contact local government extension officers when they face a disease problem. Some of them will discuss problems with their neighbour, fry trader, feed salesperson, hatchery owner or drug salesperson. Farmers feel that information from government extension officers is useful and reliable.
On encountering a disease problem, most of the farmers (54%) attempted to treat the animals. Some of farmers sought help or conducted emergency harvesting and marketing. The most common types of treatment used are chemicals and antibiotics. The average cost of treatment is US$46, and only three farmers said that the treatment was "always successful."
About 50% of the target group of this survey are categorised as poor, based
on an income of less than US$1/day/person. The major problem that causes severe
loss for small-scale aquaculture in Thailand is flooding. Disease is another
important factor affecting the income of small-scale farmers. Fisheries officers
at the provincial level have good connections with farmers; therefore, regular
training programmes on general fish health and basic disease diagnosis for fisheries
officers is a means to disseminate information to farmers.