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Tilapia has become the third most important fish in aquaculture after carp and salmon; worldwide production exceeded 1,500,000 metric tons in 2002 and increases annually. Because of their high protein content, large size, rapid growth (6 to 7 months to grow to harvest size),〔(【引用サイトリンク】title=Research & Advocacy )〕 and palatability, a number of tilapiine cichlids—specifically, various species of ''Oreochromis'', ''Sarotherodon'', and ''Tilapia''—are the focus of major aquaculture efforts. Tilapia fisheries originated in Africa. The accidental and deliberate introductions of tilapia into Asian freshwater lakes have inspired outdoor aquaculture projects in various countries with tropical climates, most notably Honduras,〔()〕 Papua New Guinea, the Philippines and Indonesia.〔()〕 Tilapia farm projects in these countries have the highest potential to be "green" or environmentally friendly. In temperate zone localities, tilapia farmers typically need a costly energy source to maintain a tropical temperature range in their tanks. One relatively sustainable solution involves warming the tank water using waste heat from factories and power stations. Tilapiines are among the easiest and most profitable fish to farm due to their omnivorous diet, mode of reproduction (the fry do not pass through a planktonic phase), tolerance of high stocking density, and rapid growth. In some regions the fish can be raised in rice fields at planting time and grow to edible size (12–15 cm, 5–6 inches) when the rice is ready for harvest. Unlike salmon, which rely on high-protein feeds based on fish or meat, commercially important tilapiine species eat a vegetable or cereal-based diet. Tilapia raised in inland tanks or channels are considered safe for the environment, since their waste and disease is contained and not spread to the wild. However, tilapiines have acquired notoriety as being among the most serious invasive species in many subtropical and tropical parts of the world. For example, ''Oreochromis aureus'', ''O. mossambicus'', ''Sarotherodon melanotheron melanotheron'', ''Tilapia mariae'', and ''T. zilli'' have all become established in the southern United States, particularly in Florida and Texas.〔(Non-Native Aquatic Species Summaries )〕 Commercially grown tilapia are almost exclusively male. Being prolific breeders, female tilapia in the ponds or tanks will result in large populations of small fish. Whole tilapia can be processed into skinless, boneless (PBO) fillets: the yield is from 30% to 37%, depending on fillet size and final trim.〔(Commercial raised and processed Tilapia )〕 == Nutritional value == Tilapia from aquaculture contain especially high ratios of omega-6 to omega-3 fatty acids. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Aquaculture of tilapia」の詳細全文を読む スポンサード リンク
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