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Abstract The marine world extends from the ocean to the deepest bed and from the shore to distant shore. Fishes represent one of the major controversial components due to their importance both from economic and human health according to the variety and difference in their role on several levels: Fishes are the most numerous and diverse of the major vertebrate groups. They dominate the waters of the world through a marvelous variety of morphological, physiological, behavioral patterns. Their diversity is reflected in the large number of living species. Moyle et al. (2000) pointed that about 200 new fish species are being described each year and the total may reach 30,000 or more. Fishes represent more than 58% from living marine ecosystem (Moyle et al., 2000; Rubio-Godoy, 2007). Fishes are valuable sources of high grade protein and organic products. Also, fish in terms of good value rank and mostly superior having less amount of fats, represents the excellent sources of polyunsaturated fatty acids and more or equal protein as compared to other fleshes consumed as food by human beings (Haruna, 2006; Staniskiene et al., 2006; Salawu et al.,2013; Singh, et al., 2013).Fishes occupy a significant position in the socio-economic status at great sectors of countries by providing the population not only the nutritious food but also income and employment opportunities, contribution to economic growth and human welfare, stimulation growth of a number of subsidiary industries and contribution to the livelihood of a large section of economically underprivileged population (Ayyapan &Krishanan, 2004). Fish is a renewable source of wealth. Unlike minerals and other fixed resources which do not have self-generating capacity to replenish the loss due to natural causes and human exploitation. Fish has a therapeutic value; from the positive side, modest doses of sea foods a week, significantly prevent the coronary heart diseases, also reduces the tendency of blood to clot and helps lower cholesterol levels in the blood (Shaukat, 2008). Moreover, from the negative side, several fishes represent a pathogenic agent for human due to transmission of several helminths parasites represented by “the anisakid nematodes (particularly Anisakis simplex and Pseudoterranova decipiens), cestodes of the genus Diphyllobothrium and digenetic trematodes of the families Heterophyidae, Opisthorchiidae and Nanophyetidae. Seafood-associated infections by acanthocephalans are rarely reported in humans” (Adams et al.,1997).Most fish species have at least some direct monetary value, are part of food webs that support economically important species, or live in environments whose good health is essential for the support of fisheries (Shaukat, 2008) The cultural values of fishes include two wide values; 1) The first one is the scientific values of fish which are obvious to Ichthyologists who find the study of fish essentially interesting. 2) The second one is the educational values of fish which are also obvious where fishes are the one group of vertebrates in which it is really possible to maintain large populations in the laboratory for observation and experimentation. Many varieties are readily available for dissection, giving an easy overview of the several types of adaptations possible in vertebrates. Most important is that they can typically be found in large numbers and diversity in waters fairly close to most educational institutions, so that many types of ecological demonstrations can be made. Fish have the right combination of availability, size and ease of handling tomake them the most desirable group of vertebrates for comparative classroom studies of ecology, behavior, evolution and anatomy, and to be very valuable in other areas such asgenetic and physiology as well. |