Several characteristics distinguish these three genera, but possibly the most critical relates to reproductive behaviour. All tilapia species are nest builders; fertilised eggs are guarded in the nest by a brood parent. Species of both Sarotherodon and Oreochromis are mouth brooders; eggs are fertilised in the nest but parents immediately pick up the eggs in their mouths and hold them through incubation and for several days after hatching. In Oreochromis species only females practice mouth brooding, while in Sarotherodon species either the male or both male and female are mouth brooders.
During the last half century fish farmers throughout the tropical and semi-tropical world have begun farming tilapia. Today, all commercially important tilapia outside of Africa belong to the genus Oreochromis, and more than 90 percent of all commercially farmed tilapia outside of Africa are Nile tilapia. Less commonly farmed species are Blue tilapia O. Mossambicus and the Zanzibar tilapia O. The scientific names of tilapia species have been revised a lot in the last 30 years, creating some confusion.
The scientific name of the Nile tilapia has been given as Tilapia nilotica , Sarotherodon niloticus , and currently as Oreochromis niloticus. Tilapia are shaped much like sunfish or crappie but can be easily identified by an interrupted lateral line characteristic of the Cichlid family of fishes.
They are laterally compressed and deep-bodied with long dorsal fins. The forward portion of the dorsal fin is heavily spined. Spines are also found in the pelvis and anal fins. There are usually wide vertical bars down the sides of fry, fingerlings, and sometimes adults. The main cultured species of tilapia usually can be distinguished by different banding patterns on the caudal fin.
Nile tilapia have strong vertical bands, Blue tilapia have interrupted bands, and Mozambique tilapia have weak or no bands on the caudal fin. Male Mozambique tilapia also have upturned snouts. Colour patterns on the body and fins also may distinguish species. Mature male Nile tilapia have gray or pink pigmentation in the throat region, while Mozambique tilapia have a more yellow colouration.
However, colouration is often an unreliable method of distinguishing tilapia species because environment, state of sexual maturity, and food source greatly influence colour intensity. The red tilapia has become increasingly popular because its similar appearance to the marine red snapper gives it higher market value.
The original red tilapias were genetic mutants. The first red tilapia, produced in Taiwan in the late s, was a cross between a mutant reddish- orange female Mozambique tilapia and a normal male Nile tilapia. It was called the Taiwanese red tilapia. Another red strain of tilapia was developed in Florida in the s by crossing a normal coloured female Zanzibar tilapia with a red-gold Mozambique tilapia.
A third strain of red tilapia was developed in Israel from a mutant pink Nile tilapia crossed with wild Blue tilapia. All three original strains have been crossed with other red tilapia of unreported origin or with wild Oreochromis species.
Consequently, most red tilapia in the Americas are mosaics of uncertain origin. The confused and rapidly changing genetic composition of red tilapia, as well as the lack of head-to-head growth comparisons between the different lines, make it difficult for a producer to identify a best red strain. Other strains of tilapia selected for colour include true breeding gold and yellow Mozambique lines and a Rocky Mountain white tilapia a true breeding line originating from an aberrant Blue tilapia, subsequently crossed with Nile tilapia.
Most strains selected for colour do not grow well enough for food fish culture. Identifying the species of an individual fish is further complicated by natural crossbreeding that has occurred between species. Electrophoresis is often used to determine the species composition of a group of tilapia.
Reproduction In all Oreochromis species the male excavates a nest in the pond bottom generally in water shallower than 3 feet and mates with several females. After a short mating ritual the female spawns in the nest about two to four eggs per gram of brood female , the male fertilises the eggs, and she then holds and incubates the eggs in her mouth buccal cavity until they hatch. Fry remain in the females mouth through yolk sac absorption and often seek refuge in her mouth for several days after they begin to feed.
Sexual maturity in tilapia is a function of age, size and environmental conditions. The Mozambique tilapia reaches sexual maturity at a smaller size and younger age than the Nile and Blue tilapias.
Tilapia populations in large lakes mature at a later age and larger size than the same species raised in small farm ponds. Under good growth conditions this same species will reach sexual maturity in farm ponds at an age of 5 to 6 months and 5 to 7 ounces to grams.
When growth is slow, sexual maturity in Nile tilapia is delayed a month or two but stunted fish may spawn at a weight of less than 1 ounce 20 grams. Under good growing conditions in ponds, the Mozambique tilapia may reach sexual maturity in as little as 3 months of age, when they seldom weigh more than 2 to 4 ounces 60 to grams.
Fish farming strategies that prevent overcrowding and stunting include: Cage farming where eggs fall through the mesh to the pond bottom before the female can collect them for brooding Polyculture with a predator fish, such as fingerling largemouth bass, at per acre Culture of only males monosex.
All-male culture is desirable in ponds not only to prevent overpopulation and stunting but also because males grow about twice as fast as females. Methods of obtaining predominately male fish include: Sponsor message. Aquaculture is an increasingly important source of safe, nutritious, and sustainable seafood for people worldwide.
Globally, aquaculture production must double by to keep pace with demand. These increases in demand for aquaculture products, food security considerations, and job creation have generated an increased need for skilled workers. Discover how you can be part of this rapidly expanding industry. The sex of a 1-ounce gram tilapia fingerling can be determined by examining the genital papilla located immediately behind the anus Fig 1.
In males the genital papilla has only one opening the urinary pore of the ureter through which both milt and urine pass. Nile Tilapia is among the most responsibly farmed fish you can buy and is widely available grocery stores and restaurants across the America stores like Costco, Kroger, HEB, Sprouts, Red Lobster, Bonefish Grill, Rubios and many others. The adaptability of this species means that it can also live in saltwater, although it thrives in freshwater.
Blue Tilapia takes much longer to reach maturity than Nile Tilapia and commonly reaches two to four pounds within three years.
This species of Tilapia is native to Africa and was introduced to the United States for sport fishing and even as a means of aquatic plant control. This species is easily recognizable because of its olive-gray tone and yellow belly. Mozambique Tilapia sits comfortably in the middle of Blue Tilapia and Nile Tilapia in terms of growth rate and weight. This species can reach over two pounds in one year.
Their fish raised in pristine lakes and are fed a vegetable-based floating feed to ensure supreme quality. Producers employ selective breeding techniques to cultivate a strong fish. This tilapia grows faster than other tilapia varieties, and is easy to grow and farm. It also resists disease and is largely available in Asia and Africa. The U. Department of Agriculture's MyPlate guidelines list t ilapia as a fish rich in protein, with more than 20 grams g per small fillet.
Here are the nutrition stats for about a 3-ounce oz cooked fillet: 5. Salmon A 3-oz fillet of cooked sockeye salmon has calories, 23g of protein, and 5g of fat. The difference is in the fat. Salmon is a fatty fish, and it has nearly 3 times the fat of tilapia. But salmon also has to 1, milligrams mg of heart-healthy omega-3 fatty acids per portion. In contrast, tilapia contains less than mg.
Cod Like tilapia, cod is another flaky white fish, so one easily substitutes for the other. In terms of nutrition, a 3-oz piece of cooked cod rings in slightly lower in calories 89 , protein 19g , and fat less than 1g. For example, wild bluefin tuna contains 1, to 1,mg of omega-3s; canned white albacore tuna has between and 1,mg; and canned light tuna and wild skipjack tuna have between and mg. Tilapia can be part of a weight loss diet. The foremost reason: Its protein content.
With 23g of satiating protein per 3-oz, calorie fillet, it will keep you full, possibly helping you resist less-healthy between-meal snacks. Research in short-term studies shows that people on higher-protein calorie-restricted diets lose more weight and fat compared with similar diets lower in protein.
Ideally, eating 25 to 30g of protein per meal is best to decrease appetite and spur weight loss. Having whole grain and vegetable sides along with the fish fillet will get you to that 25g marker easily. You can buy raw tilapia fresh from the fish counter at your grocery store or individually wrapped as frozen fillets in the frozen-foods section. When it comes to selecting fish, including tilapia, you want to buy based on quality and appearance, as well as environmental impact.
When choosing tilapia, look for fillets that have firm, shiny flesh. Some will have been previously frozen, which is completely fine. If possible, store in a cooler for the trip home. Specifically, you can look for those that are raised in indoor recirculating tanks worldwide , ponds from Ecuador or raceway farms from Peru if you want to find the greenest option.
You can also look for eco certifications. These may be listed on the label or the front of the package of frozen tilapia.
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