Summary of academic and scholastic contributions

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Professor Shiau is well recognized by his broad-base and in-depth research on the nutrition of grass shrimp, tilapia and grouper. Through his efforts and accomplishments, Taiwan is internationally known as a world frontier in shrimp and fish nutrition research.

1. The establishment of the requirements of niacin, biotin, folic acid, pantothenic acid, ascorbic acid, choline, pyridoxine, inositol, vitamin A, vitamin D, vitamin E and vitamin K of grass shrimp by Prof. Shiau provides comprehensive basic vitamin nutrition information for the aquatic animal nutrition community. L-ascorbic acid (AA) was traditionally used as a vitamin C source in aquatic feeds. However, AA is unstable and practical diets have been shown to lose AA during processing and storage. Prof. Shiau successfully established the biopotency of the four stable derivatives of AA, namely L-ascorbyl-2-sulfate (C2S), L-ascorbyl-2-monophosphate-Mg (C2MP-Mg), L-ascorbyl-2-monophosphate-Na (C2MP-Na), and L-ascorbyl-2-polyphosphate (C2PP), in meeting the vitamin C requirement of grass shrimp.

2. Tilapia has recently been recognized by the FAO as the most important culture fish in the world for supplying human protein in the 21st Century. Prof. Shiau began his tilapia nutrition program in 1985. Since then, adequate protein/energy ratio, carbohydrate utilization, and lipid, vitamin and mineral requirements of tilapia have been accomplished.

(1) Dr. Shiau is a pioneer in fish carbohydrate utilization research. He has identified several abiotic and biotic factors that relate to carbohydrate utilization by tilapia, especially with regard to chromium and chromic oxide effects. His publications in this aspect challenge the conventional wisdom in the field of fish nutrition that chromic oxide is an acceptable inert marker which has been used extensively as an external marker to determine the digestibility of fish feed ingredients.

(2) Tilapia used to be categorized as the model fish species that requires only ω-6 fatty acid for growth. Prof. Shiau demonstrated that tilapia requires both ω-6 and ω-3 fatty acids. The finding has led to the reassessment of fatty acid requirements of the fish, and also to re-evaluate a more accurate vitamin E requirement for the species.

(3) Prof. Shiau found that ferric citrate was about 50% as effective as ferrous sulfate in meeting the iron requirement for tilapia- an important discovery in mineral availability in fish.

3. Grouper are a high quality seafood in Asia and around the world. They are also good candidates for intensive aquaculture because of their desirable taste, hardiness in a crowded environment and rapid growth. However, the nutritional information for this species is scarce. Through Prof. Shiau’s efforts, protein, lipid, fatty acid, vitamin C, vitamin E, inositol, selenium and copper requirements of grouper have been established.

(1) Prof. Shiau found that grouper had similar utilization of complex and simple carbohydrates. He also found that water temperature affects carbohydrate utilization by grouper.

(2) Prof. Shiau has quantified the vitamin C requirements for grouper by using various vitamin C sources, such as (in mg AA/kg diet): 45.3 (AA), 17.9 (C2MP-Mg), 8.3 (C2MP-Na), 17.8 (C2PP) and 46.2 (C2S). The biopotency of the four AA derivatives for grouper was calculated as: C2MP-Na (1) > C2PP (84%) > C2MP-Mg (46%) > C2S (32%).

(3) By defining nutrient requirements only for their potential to maximize the animal’s growth, the first revolution of nutrition research largely ignored the role of nutrients in disease prevention. Recently, evidence has shown the relationship between nutritional factors and immune function in animals. Prof. Shiau demonstrated that lipids, fatty acids, vitamins C and E, Se and nucleotides can influence various parameters of the immune response and disease resistance in grouper.

Grass shrimp, tilapia and grouper are the most valuable indigenous aquatic species in Taiwan and are significant culture species worldwide. Prof. Shiau’s research concerning these species has made him an internationally recognized authority in fish and shrimp nutrition. This recognition has led to his appointment as a conference and workshop organizer and as a keynote/plenary speaker at various conferences. He has been invited to write several book chapters and serve on the Editorial Advisory Board of three major international journals (Aquaculture, Aquaculture Nutrition, and Aquaculture Research). Additionally, he served as Board Director of the World Aquaculture Society (2001-2004) and was nominated to serve as a committee member of the National Research Council (NRC) of the National Academy of sciences, USA for "Nutrient Requirements of Fish and Shrimp" in 2009. Prof. Shiau currently serves as a member of the Fish and Shellfish Committee of the International Union of Nutritional Sciences , the Councilor and Editor-in-Chief for the Asian Fisheries Society, and as a newly appointed Editor for the journal Aquaculture Research in July 2010.