The attention of the scientific and professional communities, as well as of food consumers, has always been directed towards finding adequate nutritional strategies that could improve food production and safety. By using antibiotics as feed additives, farmers gained increased profits based on higher growth rates with better feed conversion and lower costs of therapeutic treatment. The quantities of antibiotics used as growth promoters for farm animals have been increasing constantly, but at the same time, the frequency of bacterial resistance to antibiotics and the presence of antibiotic residues in food have become a global problem. To eliminate or minimize these risks, on 1 January 2006, antibiotics were banned from use as additives in animal nutrition in the European Union. Accordingly, there is interest in developing new nutritional strategies that would support the function of the autochthonous microbiota in the animal gastrointestinal tract to control pathogenic bacteria. Probiotics, prebiotics, phytobiotics and feed enzymes are a new generation of growth promoters and largely achieve their effects by using the physiological mechanisms of animals and/or their intestinal microbiomes, enabling animals to completely fulfil their genetic potential with respect to production properties.
The aim of this study was to determine the content of some elements (Pb, Cd, Hg, Fe, Cu, Zn, As) in muscle tissue of Prussian carp (Carassius auratus gibelio) from seven different lakes in the Belgrade region, Serbia. Concentrations of Pb, Hg and As in fish muscle tissues from all examined lakes were under the maximum residual levels prescribed by the European Union (EU) and the maximum allowed concentrations (MAC) for Serbia. In all investigated fish, levels of Cd exceeded maximum allowed concentrations (0.05 mg kg-1). Data on the finding of elements in fish speak concurrently about the safety of fish as food and are good indicators of environmental pollution.
The aim of this study was the investigation of water, sediments and fish tissues contamination with heavy metals. All samples were taken from the Danube River in Belgrade region, a location upstream from Batajnica. Concentrations of Cd, Hg and Pb in water samples were not detected, while concentrations of Zn, Fe, Cu and As were in the range of 0.004 - 0.330 mg L-1. Iron was the most deposited metal in sediment samples in contrast to water samples where all investigated metals were detected. For the purpose of heavy metals determination in fresh fish tissue, fifteen samples of three different fish species, silver carp (Hypophthalmichthys molitrix), common carp (Cyprinus carpio) and wels catfish (Silurus glanis) were collected. Concentrations of Pb, Cd, As and Hg were determined in the digestive tract, liver and muscle by absorption spectroscopy. The highest concentration of Pb was in the digestive tract in all three fish species, ranging from 0.036 to 1.518 μg g-1, while Cd was mostly deposited in the liver. Concentrations of As were in the range of 0.36 - 0.73 μg g-1 in Hypophthalmichthys molitrix, 0.013 - 0.18 μg g-1 in Cyprinus carpio and 0.003 - 0.005 μg g-1 in Silurus glanis tissues, while the content of Hg was equal in all tested tissues of carp. Concentrations of all metals were found to be present in the fish samples at different levels, but these values are under the maximum residual levels prescribed by the European Union (EU) and the maximum allowed concentrations (MAC) for Serbia, so the fish meat is acceptable for the human consumption. ; Cilj ovog rada je ispitivanje kontaminacije teškim metalima vode, sedimenta kao i tri različite vrste sveže ribe. Svi uzorci su uzeti iz Dunava u regionu Beograda, tačnije uzvodno od Batajnice. Koncentracije Cd, Hg i Pb u uzorcima vode su približne graničnim vrednostima detekcije, dok su koncentracije Zn, Fe, Cu i As u opsegu 0.004 - 0.330 mg L-1. Gvožđe je najprisutniji metal u uzorcima sedimenata za razliku od uzoraka vode gde su svi ispitivani metali podjednako zastupljeni. U cilju ispitivanja teških metala u tkivima riba sakupljeno je po petnaest uzoraka tri različite vrste riba, tolstolobika (Hypophthalmichthys molitrix), šarana (Cyprinus carpio) i soma (Silurus glanis). Koncentracije Pb, Cd, As i Hg određene su u digestivnom traktu, jetri i mišićnom tkivu sveže dunavske ribe metodom absorpcione spektroskopije. Najveća koncentracija Pb zabeležena je u digestivnom traktu kod svih ispitivanih vrsta riba i to u opsegu 0.036 - 1.518 μg g-1, dok je Cd uglavnom deponovan u jetri. Koncentracija As bila je u opsegu 0.36 - 0.73 μg g-1 u tkivu Hypophthalmichthys molitrix, 0.013 - 0.18 μg g-1 u tkivu Cyprinus carpio i 0.003 - 0.005 μg g-1 u tkivu Silurus glanis, dok je sadržaj Hg bio izjednačen u svim ispitivanim tkivima šarana. Koncentracije svih metala u tkivima riba su različite i ispod maksimalno dozvoljenih koncentracija predvidjenih pravilnikom Evropske Unije i maksimalno dozvoljenih koncentracije (MDK) u Srbiji, a riba može da se koristi za ishranu ljudi.
The aim of this study was the investigation of water, sediments and fish tissues contamination with heavy metals. All samples were taken from the Danube River in Belgrade region, a location upstream from Batajnica. Concentrations of Cd, Hg and Pb in water samples were not detected, while concentrations of Zn, Fe, Cu and As were in the range of 0.004 - 0.330 mg L-1. Iron was the most deposited metal in sediment samples in contrast to water samples where all investigated metals were detected. For the purpose of heavy metals determination in fresh fish tissue, fifteen samples of three different fish species, silver carp (Hypophthalmichthys molitrix), common carp (Cyprinus carpio) and wels catfish (Silurus glanis) were collected. Concentrations of Pb, Cd, As and Hg were determined in the digestive tract, liver and muscle by absorption spectroscopy. The highest concentration of Pb was in the digestive tract in all three fish species, ranging from 0.036 to 1.518 μg g-1, while Cd was mostly deposited in the liver. Concentrations of As were in the range of 0.36 - 0.73 μg g-1 in Hypophthalmichthys molitrix, 0.013 - 0.18 μg g-1 in Cyprinus carpio and 0.003 - 0.005 μg g-1 in Silurus glanis tissues, while the content of Hg was equal in all tested tissues of carp. Concentrations of all metals were found to be present in the fish samples at different levels, but these values are under the maximum residual levels prescribed by the European Union (EU) and the maximum allowed concentrations (MAC) for Serbia, so the fish meat is acceptable for the human consumption.
