World Aquaculture 25 diversification of the Czech fish market; however, their proportion to the total fish production is rather less important. Microalgae Culture At present, the culture of planktonic microalgae is the aquaculture sector of obvious rising importance. Live microalgae play a key role in aquaculture, being the feed source for rotifers, crustaceans and fish larvae. There are a number of different modes where microalgae are used in fish aquaculture as sources of biomass – directly as an unprocessed sole component (live feed or green water) to build up food chains, or in the form of dried material added to pelleted or otherwise processed feed. Algal biomass has a high content of pigments, proteins, lipids, minerals and vitamins, including polyunsaturated fatty acids (PUFAs) and carotenoids, which are essential for nutrition and protection. At present, microalgae are cultivated on an experimental scale in closed or semi-closed systems – photobioreactors with natural or artificial sources of light – or in open, large-scale outdoor systems, as sources of bulk biomass (Figure 15). Aquaculture Research At the end of the first decade of the 21st century, aquaculture research in the Czech Republic is concentrated at universities and in the Czech Academy of Sciences. The Faculty of Fisheries and Protections of Waters, University of South Bohemia plays the leading role in aquaculture research and university education in the Czech Republic. Generally, the research is focused on three basic areas: 1. Biological aspects of aquaculture diversity related to molecular, cytogenetic, cytometric, hematological and reproductive levels of diploid, polyploid and monosex fish populations, hereditary traits of fish, levels of endocrinological processes in fish reproduction, and cryopreservation of gametes and embryos. 2. Environmental aspects of aquaculture with emphasis on the impact of contaminants on the aquatic environment of fish, including assessment of the level of contamination and the prevention and elimination of health risks in fish farms. 3. Breeding aspects of aquaculture and issues associated with intensive fish farming, new methods for aquaculture farming, influence of piscivorous predators on pond aquaculture, and fish meat quality, as related to their nutrition. Education Vocational and complete secondary education in fisheries, aquaculture, water management and aquatic ecology is provided by three fisheries secondary schools. School graduates find employment in fish farming enterprises, fisheriesassociated industries and aquarium entrepreneurship, as well as professionals in anglers unions, river management authorities, state authorities and administration focused on environmental conservation and water protection. University education in fisheries is provided by two universities, the Mendel´s University in Brno (MU) and the University of South Bohemia in České Budějovice (USB). Both facilities also organize professional training courses, seminars, national and international workshops and conferences. Fig. 13. Marketable mirror (top) and scaly (below) common carp. (Photo by David Hlaváč.) Fig. 14. Tench, silver carp, and grass carp (from top to bottom) are important fish species of pond polyculture. (Photo by David Hlaváč.) Fig. 15. Outdoor large-scale cascade unit for cultivation of the microalga Chlorella vulgaris that is used as food and feed supplement (Institute of Microbiology, Třeboň, Czech Republic).
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