Program and Abstracts(PDF)

Presentation 14
FISH NUTRITION AND FISH HEALTH -RECENT PROGRESS IN JAPAN-
Shunsuke Koshio
Faculty of Fisheries, Kagoshima University, Shimoarata, Kagoshima, 890-0056, Japan
Email: koshio@fish.kagoshima-u.ac.jp
Nutrition is very important to maintain health and recover from illness and to improve the
resistance against disease and stress in aquatic animals like other animals. Optimal feeds can
provide animals with healthy conditions and greater stress resistance, and optimal nutrients can
change immune responses in a positive way.
Since several micronutrients such as vitamins are not synthesized or synthesized less than
required in the aquatic animal body to grow normally and maintain or promote health, those
should be provided from the feeds. Although recommended dietary levels of many nutrients for
avoiding deficiency signs and the maximum growth have been shown in several aquatic species,
there are very limited data available on the requirements and/or recommended values in terms of
improving health and quality of cultured species. Recently, several studies have demonstrated
that over-dosed vitamin intake or administration of some extracts from natural organisms
improved the stress tolerance, immunological response, and disease resistance of cultured species.
This paper introduces recent work conducted in Japan on nutritional factors affecting aquatic
animal health together with growth parameters, immunological responses, disease resistance and
so on. The focuses are as follows:
• Utilization of By-product
• Effects of Micronutrients and Functional Compounds
• Reduction of Oxidative Stress
It can be possible to enhance stress and disease resistance, and therefore aquatic animal health,
by taking vitamin concentrations which are higher than those of the requirement, useful bacteria,
and functional compounds such as immunostimulants from natural organisms and plants. On the
other hand, the universal validity on determining the optimal level of those will depend on the
condition such as nutrient types, dosage, period, timing, health status, and genetic history of
animals, etc.
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