Tilapia

Fishes in the family Salmonidae (trout and salmon) are in high demand, with the interest in salmon being greatest in developed nations. Salmon, mostiy Atiantic salmon, are produced in Canada, Chile, Norway, New Zealand, Scotiand, and the United States. Fishes in the family Cichhdae which includes several cultured species of tilapia, are reared primarily in the tropics, but have been widely introduced throughout both the developed and developing world. 

Species such as carp, salmon, trout, channel catfish, and tilapia have been bred for many generations in captivity though they usually differ httle in appearance or genetically from their wild counterparts. A few exceptions exist, such as the leather carp, a common carp strain selectively bred to produce only one row of scales, and the Donaldson trout, a strain of rainbow trout developed over numerous generations to grow more rapidly to larger size and... 

Unlike catfish, tilapia, trout and salmon, that produce several hundred to several thousand eggs per female, many marine species produce large numbers of very small eggs. Hundreds of thousands to millions of eggs are produced by such species as haUbut, flounders, red dmm, striped bass, and shrimp. Catfish, salmon, and trout spawn once a year, while tilapia and some marine species spawn repeatedly if the proper environmental conditions are maintained (1). Red dmm, for example, spawn every few days for periods of several months when light and temperature and properly controlled (10). 

Anesthetics. Ethyl amiaobenzoate [94-09-7] (benzocaiae), C2H22NO2, is the only anesthetic candidate that might allow spawned-out broodstock carcasses to be used for pet or human food. Studies are still required to determine which residues remain ia the carcasses (9). Electronarcosis is an alternative to chemical anesthesia that uses varying electrical frequencies to rapidly anesthetize fishes and allow gentie recovery. Electronarcosis has been used effectively on tilapia (Oreochromis sp.) and the common carp Cyprinus carpid) and the technique is being tested with other fishes (23,24). 

Proteinaceous phytochemicals can contain toxic epitopes that elicit defense responses for example gliaden and glutein peptides which cause celiac disease and other mucosal disorders (Tighe and Ciclitira, 1995 Van de Wal et al, 1999). The mucosal inflammation caused by feeding carnivorous Atlantic salmon diets with soybean meal decreases rates of nutrient absorption (Nordrum et al, 2000), whereas the detrimental influence of such diets is much less pronounced when fed to omnivorous fish, such as catfish and tilapia. 

Arnold BS. 2000. Distribution of mercury within different trophic levels of the Okefenokee swamp, within tissues of top level predators, and reproductive effects of methyl mercury in the Nile tilapia (Oreochromis niloticus). PhD dissertation. University of Georgia. 

Bainy ACD, Saito E, Carvalho PSM, Junqueira VBC (1996) Oxidative stress in gill, erythrocytes, liver and kidney of Nile tilapia (Oreochromis niloticus) from a polluted site. Aquat Toxicol 34 151-162... 

Hwang, P.P., S.W. Lin, and H.C. Lin. 1995. Different sensitivities to cadmium in tilapia larvae (Oreochromis mossambicus teleostei). Arch. Environ. Contam. Toxicol. 29 1-7. 

Shiau, S.Y. and M.J. Chen. 1993. Carbohydrate utilization by tilapia (Oreochromis niloticus X O. aureus) as influenced by different chromium sources. Jour. Nutr. 123 1747-1753. 

Wepener, V., J.H.J. van Vuren, and H.H. Du Preez. 1992. The effect of hexavalent chromium at different pH values on the haematology of Tilapia sparrmanii (Cichlidae). Comp. Biochem. Physiol. 101C 375-381. 

Copper concentrations in freshwater fishes collected nationwide in the United States have not changed significantly since 1978 (Schmitt and Brumbaugh 1990). In 1984, samples with the highest copper concentrations were Mozambique tilapia (Tilapia mossambica) from Hawaii and white perch (Morone americana) from the Susquehanna River in Maryland. These locations have historically... 

Pelgrom, S.M.G.J., L.P.M. Lamers, J.A.M. Garritsen, B.M. Pels, R.A.C. Lock, P.H.M. Balm, and S.E.W. Bonga. 1994. Interactions between copper and cadmium during single and combined exposure in juvenile tilapia Oreochromis mossambicus influence of feeding condition on whole body metal accumulation and the effect of the metals on tissue water and ion content. Aquat. Toxicol. 30 117-135. 

Mozambique tilapia, Oreochromis niloticus 330 pg/L for 240 h lymphocytes and blood plasma lactate levels most blood chemistry variables were normal Whole body concentration of 14.9 mg Pb/kg FW 31... 

Ghazaly, K.S. 1991. Influences of thiamin on lead intoxication, lead deposition in tissues and lead hematological responses of Tilapia zillii. Comp. Biochem. Physiol. 100C 417-421. 

Canli, M. and F. Kargin. 1995. A comparative study on heavy metal (Cd, Cr, Pb and Ni) accumulation in the tissue of the carp Cyprinus carpio and the Nile fish Tilapia nilotica. Turkish Jour. Zool. 19 165-171. 

Ghazaly, K.S. 1992. Sublethal effects of nickel on carbohydrate metabolism, blood and mineral contents of Tilapia nilotica. Water Air Soil Pollut. 64 525-532. 

Chliamovitch, Y.P. and C. Kuhn. 1977. Behavioural, haematological and histological studies on acute toxicity of bis(tri-n-butyltin)oxide on Salmo gairdneri Richardson and Tilapia rendalli Boulenger. Jour. Fish Biol. 10 575-585. 

Tilapia, Tilapia sparrmanii, adults, exposure for 72 h Bolti, Tilapia zilli 98,000 Decreased oxygen consumption, mucus precipitation on gills, histopathology of gill epithelium 79... 

Hilmy, A.M., N.A. El-Domiaty, A.Y. Daabees, and H.A.A. Latife. 1987. Toxicity in Tilapia zilli and Clarias lazera (Pisces) induced by zinc, seasonally. Comp. Biochem. Physiol. 86C 263-265. 

Banded tilapia, Tilapia sparrmanii 310-6700 Sublethal effects after 72 h include decreased activity, color changes, coughing, and maximum blood atrazine concentrations of about 3 mg/L 20... 

Mozambique tilapia, Tilapia mossambicus 1100 No deaths in 90 days. Increased growth and body water content disrupted serum electrolytes 23... 

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