Like other large fish, they are a good source of protein and popular among artisanal and commercial fisheries. Most such fisheries were originally found in Africa, but outdoor fish farms in tropical countries such as, the plipine, and indonesia are underway in freshwater lakes. In temperture zonelocalities, tilapiine farming operations require energy to warm the water to tropical temperatures. One method uses waste heat from factories and powerstation.
China is the largest Tilapia producer in the world, seconded by Egypt
Commercially grown tilapia are almost exclusively male. Cultivators use hormones such as testosterone to reverse the sex of newly spawned females. Because tilapia are prolific breeders, the presence of female tilapia results in rapidly increasing populations of small fish, rather than a stable population of harvest-size animals.
|tilapia fish pond|
Whole tilapia fish can be processed into skinless, boneless fillets: the yield is from 30 percent to 37 percent, depending on fillet size and final trim.The use of tilapia in the commercial food industry has led to the virtual extinction of genetically pure bloodlines. Most wild tilapia today are hybrids of several species.
Increasing stocking densities places increasing demands on the production system. Additional energy inputs in the form of labor, water exchange, aeration and feeds are all required to sustain the intensive system. As pond production intensifies and feed rates increase, supplemental aeration and some water exchange are required to maintain good water quality. For densities above 1.5-kg per square meter, aeration is usually required. There is a point where the incremental returns are not worthy of the additional inputs and risks. Increasing the intensity of the system does not necessarily reflect an increase in profitability.
All tilapia production systems must provide a suitable environment to promote the growth of the aquatic crop. Critical environmental parameters include the concentrations of dissolved oxygen, un-ionized ammonia nitrogen, nitrite nitrogen, and carbon dioxide in the water. Other important parameters include nitrate concentration, pH, and alkalinity levels within the system. To produce tilapia in a cost effective manner, production systems must be capable of maintaining proper levels of these water quality variables during periods of rapid fish growth. To provide for such growth, tilapia are fed high protein pelleted diets at rates ranging from 1.0% to 30% of their body weight per day depending upon their size and species.
Numerous options for holding broodfish, fry, fingerlings, juveniles, sub-adult and adult tilapias are available to the prospective farmer. The options include ponds, tanks, raceways, hapas and cages. Tanks and raceways involve considerably greater expense to construct but offer greater control. They are usually used in intensive and super-intensive culture of tilapias. Ponds are much cheaper to construct and allow management to stimulate natural productivity more readily. The major drawback of pond culture of tilapias is the greater risk of uncontrolled reproduction, which will occur if certain measures are not taken to minimize this possibility. Ponds are used in extensive, semi-intensive and intensive tilapia production. Pond culture is by far the most common method being employed throughout Latin America because it is the cheapest method and also is one of the best.
Ponds are the traditional and inexpensive way to hold spawning populations of broodfish. In some parts of the world, the pond system has been made more efficient through the use of cages or net enclosures (hapas). Basically, the hapas are fine mesh net enclosures that are about 40 square meters in size and arranged into units within a larger pond. This segregates the pond into more easily managed units. On a per unit area basis, tanks are the most efficient method of collecting and raising fry, followed by hapas and simple ponds.
In aquaculture, no two situations are alike. Each project must be carefully crafted to meet the expectations of the owners, while giving diligent consideration to the limitations and strengths inherent in the proposed venture.
Marketing the Product
The total aquaculture production of tilapia was reported to be 1,265,800 tons in 2000. International trade is growing rapidly, especially between Central American producers (Costa Rica, Ecuador and Honduras) and the United States, and between Asian producers (Taiwan, China, Indonesia and Thailand) and the United States and Japan. There is also modest trade between Jamaica and the United Kingdom. The largest exporter, Taiwan, supplies Japan with high-quality tilapia fillets for the sashimi market, and ships frozen tilapia to the United States market (40,000 tons in 2001). Taiwan exports about 70 percent of its domestic tilapia production. Thailand and Indonesia export less than 5 percent of their production.