Tilapia has become the third most important fish in aquaculture after carps and salmonids, with production reaching 1,505,804 metric tons in 2002.[1] Because of their large size, rapid growth (six to seven months to grow to harvest size,[2]) and palatability, a number of tilapiine cichlids are at the focus of major aquaculture efforts, specifically various species of Oreochromis, Sarotherodon, and Tilapia, collectively known colloquially as tilapias. Like other large fish, they are a good source of protein and a popular target for artisanal and commercial fisheries. Originally, the majority of such fisheries were in Africa, but accidental and deliberate introductions of tilapia into freshwater lakes in Asia have led to outdoor aquaculturing projects in countries with a tropical climate, such as Papua New Guinea, the Philippines, and Indonesia.[1] In temperate zone localities, tilapiine farming operations require energy to warm the water to the tropical temperatures these fish require. One method involves warming the water using waste heat from factories and power stations.[3]
Tilapiines are also 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 put out in the rice fields when rice is planted, and will have grown to edible size (12–15 cm, 5–6 inches) when the rice is ready for harvest. One recent estimate for the FAO puts annual production of tilapia at about 1.5 million tonnes, a quantity comparable to the annual production of farmed salmon and trout.[2] Unlike salmon, which rely on high-protein feeds based on fish or meat, commercially important tilapiine species eat a vegetable or cereal-based diet. Tilapias raised in inland tanks or channels are considered safe for the environment, since their waste and disease should be contained and not spread to the wild.[4]
Set against their value as food, 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.[5]
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.[6]
Contents |
Tilapia from aquaculture contain more fat and a much higher ratio of omega-6 to omega-3 oils.
Apart from the very few species found in the Levant, such as the Middle Eastern mango tilapia, there are no tilapiine cichlids endemic to Asia. However, species originally from Africa have been widely introduced and have become economically important as food fish in many countries. China, the Philippines, Taiwan, Indonesia and Thailand are the leading suppliers, and these countries altogether produced about 1.1 million metric tonnes of fish in 2001, constituting about 76% of the total aquaculture production of tilapia worldwide.[1]
In Indonesia, tilapia are known as ikan nila. Tilapia were introduced to Indonesia in 1969 from Taiwan. Later, several species also introduced from Thailand (Nila Chitralada),Philippines (Nila GIFT) and Japan (Nila JICA). Tilapia has become popular with local fish farmers because they are easy to farm and grow fast. Major tilapia production areas are in West Java and North Sumatra. In 2006, Badan Pengkajian dan Penerapan Teknologi (Agency for the Assessment and Application of Technology) and Balai Besar Pengembangan Budidaya Air Tawar (Main Center for Freshwater Aquaculture Development - MCFAD), Indonesian government research, development and introduced a new species named "genetically supermale Indonesian tilapia" (GESIT). GESIT fish are genetically engineered to hatch eggs that will produce 98% - 100% male tilapia. Monosex culture (all male) is more productive and will benefit the farmers. Now, around 14 strains of ikan nila have been developed by contributions from research institutes including MCFAD.
In Malawi a variety of tilapia, Oreochromis lidole is one of the most popular fish in Malawi. It is locally known as 'chambo' in Malawi. [7]It is endemic to Endemic to bodies of water in Malawi like Lake Malawi, Lake Malombe and the Shire River.[8] Due to over fishing, the fish however is now on the threatened species list.[9] Malawi has its fish farms that are dedicated to farming this fish.
In the Philippines, several species of tilapia have been introduced into local waterways and are farmed for food. Tilapia fish pens are a common sight in almost all the major rivers and lakes in the country, including Laguna de Bay, Taal Lake and Lake Buhi.
Locally, tilapia are also known as pla-pla. Tilapiine cichlids have many culinary uses, including fried, grilled, sinigang (a sour soup using tamarind, guava, calamansi or other natural ingredients as a base), paksiw (similar to sinigang, only it uses vinegar) and many more recipes.
On January 11, 2008, the Cagayan Bureau of Fisheries and Aquatic Resources (BFAR) stated that tilapia production grew and Cagayan Valley is now the Philippines’ tilapia capital. Production supply grew 37.25% since 2003, with 14,000 metric tons (MT) in 2007. The recent aquaculture congress found the growth of tilapia production was due to government interventions: provision of fast-growing species, accreditation of private hatcheries to ensure supply of quality fingerlings, establishment of demonstration farms, providing free fingerlings to newly constructed fishponds, and the dissemination of tilapia to Nueva Vizcaya (in Diadi town). Former cycling champion Lupo Alava has received multiple awards as a tilapia raiser in Bagabag, Nueva Vizcaya. Chairman Thompson Lantion of the Land Transportation Franchising and Regulatory Board, a retired two-star police general, has fishponds in La Torre, Bayombong, Nueva Vizcaya. Also, Nueva Vizcaya Gov. Luisa Lloren Cuaresma also entered into similar aquaculture endeavors in addition to tilapia production.[10]
In Taiwan, tilapiine cichlids are also known as the "South Pacific crucian carp", and since their introduction, have spread across aquatic environments all over the island. Introduced in 1946, tilapiine cichlids made a considerable economic contribution, not only by providing the Taiwanese people with food, but also by allowing the island's fish farmers to break into key markets, such as Japan and the United States. Indeed, tilapiine cichlids have become an important farmed fish in Taiwan for both export and domestic consumption.[11]
The Chinese name for the fish in Taiwan is wu-kuo (吳郭), and was created from the surnames of Wu Chen-hui (吳振輝) and Kuo Chi-chang (郭啟彰), who introduced the fish into Taiwan from Singapore. The Taiwan tilapia is a hybrid of Oreochromis mossambicus and O. niloticus niloticus. In mainland China, it is called luofei fish (罗非鱼), named after the origin of this fish: the Nile and Africa (niLUO and FEIzhou in Chinese respectively).
Known in Thai language as pla taptim (Thai: ปลาทับทิม), the tilapia O. niloticus is very popular in Thai cuisine.[12]
Thailand has its share of fish farms and fish pens devoted to the culture of tilapia species. In March 2007, millions of caged tilapia in the Chao Praya river died as the result of a massive fish kill. The cause for this was determined to be oxygen deprivation on a massive scale, one of the causes for fish kills.[13]
In the United States, the geographic range for tilapia culture is limited by their temperature-sensitivity. For optimal growth, the ideal water temperature range is 82 to 86°F, and growth is reduced greatly below 68°F. Death occurs below 50°F. Therefore, only the southernmost states are suitable for tilapia production. In the southern region, tilapia can be held in cages from five to 12 months per year, depending on location.[14] About 1.5 million tons of tilapia were produced in the US in 2005, with 2.5 million tons projected by 2010.[15]
|
||||||||||||||||||||||||||||||||||||||||||||||||
|
|||||||||||||||||||||||||||||