The present review gives a brief account of the toxic effects of heavy metals on fish. In aquatic ecosystem, heavy metals are considered as the most important pollutants, since they are present throughout the ecosystem and are detectable in critical amounts. Heavy metals, such as mercury, cadmium, copper, lead and zinc are of the most important pollutants which effect aquatic environment and fish. They are extremely dangerous for the health of fish. Most of these metals are characterized by being accumulated in tissues, and lead to the poisoning of fish. These metals can effectively influence the vital operations and reproduction of fish; weaken the immune system, and induce pathological changes. As such, fish are used as bio-indictors, playing an important role in monitoring heavy metals pollution. Finally, some recommendations are given to treatment of different kinds of wastewaters, sewage and agricultural wastes before discharge into the aquatic systems. Also, enforcement of laws and legislations regarding the protection of aquatic environments must be taken into consideration.

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Use of Fish as Bio-indicator of the Effects of Heavy Metals Pollution

Current knowledge in species-related bioavailability of selenium in food

Novel approaches for selenium speciation in foodstuffs and biological specimens: a review.

Meta-analysis of literature data on mineral and trace element requirements of fish was performed with the major objectives of identifying appropriate response criteria and the factors affecting the minimal dietary inclusion levels. The primary data set included 25 studies on available P, 20 on Ca, 24 on Mg, 5 on K, 37 for Zn, 23 for Se, 19 for Mn, 16 for Fe and 13 for Cu. Broken line regression analysis with linear plateau model (P, Ca, Mg and K) or two-linear line model (Zn, Cu, Fe, Mn and Se) was used for determining the minimal dietary inclusion levels. Vertebral mineral concentration (P, Ca, Zn and Mn), whole-body mineral levels (Mg, K and Fe) and hepatic enzyme activity (Se) were found to be the most appropriate criteria for the respective minerals analysed. In general, weight gain as the criterion resulted in a lower estimate (by 18–42%) than those obtained using whole-body or vertebral mineral concentrations as response criteria. The analysis also showed that different fish species do not show large variations in the mineral and trace element concentrations in the whole body and tissues. Factors such as species group and digestive physiology, type of experimental diet used and dietary interactions, type of mineral source and mineral concentration of water were found to affect the minimal dietary inclusion levels of certain minerals. Besides the meta-analysis, research needs in mineral nutrition of fish with reference to growing changes in dietary strategies and rearing systems are discussed.

Mineral requirements of fish: a systematic review

Effects of different levels of dietary selenium nanoparticles on growth performance, muscle composition, blood biochemical profiles and antioxidant status of common carp (Cyprinus carpio)

Effect of different selenium source on growth performances, glutathione peroxidase activities, muscle composition and selenium concentration of allogynogenetic crucian carp (Carassius auratus gibelio)

Yanbo Wang

Papers

Effect of different selenium source on growth performances, glutathione peroxidase activities, muscle composition and selenium concentration of allogynogenetic crucian carp (Carassius auratus gibelio)