Now showing 1 - 10 of 18
  • Publication
    Influence of farm type (organic, conventional and intensive) on toxic metal accumulation in calves in NW Spain
    (Institute of Technology, Estonian University of Life Sciences, 2006-08-27) ; ; ; ; ;
    The aim of the present study was to determine how accumulation of toxic metals by beef-cattle in NW Spain varies between farms that have markedly different practices (including intensive, conventional and organic management) and to determine possible key factors affecting toxic metal assimilation by cattle. Soil, feed (forage and concentrate) and animal tissues (liver and kidney from 120 calves) were collected from nine farms across NW Spain and were analysed for metals by ICP-MS. Toxic metal concentrations in beef calves were generally low but did vary significantly between farms. There were no consistent patterns of difference in tissue metal concentrations between farms from different regions or between farms with different management practices. Variations in arsenic, cadmium and mercury concentrations in calf tissues were not significantly explained by soil or diet metal concentrations but were significantly and inversely related to the proportion of concentrate in the ration. Higher levels of metal residues in tissues were associated with consumption of low amounts of concentrate and relatively high levels of grazing. Higher toxic metal intake due to grazing is likely to be largely a result of soil ingestion.
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  • Publication
    Influence of Cu supplementation on toxic and essential trace element status in intensive reared beef cattle
    The aim of this study is to evaluate if dietary Cu supplementation that leads to a hepatic Cu accumulation over the normal range has an influence on trace element status that could contribute to the pathogenesis of other mineral related disorders. Samples (liver, kidney, spleen, diaphragm and brain) of beef calves receiving typical commercial diets Cu supplemented and non-supplemented were tested for differences in non-essential and essential trace elements determined by ICP-MS. As (kidney and diaphragm), Hg (liver and kidney), and Pb (liver, kidney and spleen) were significantly lower, while Cd residues (liver and kidney) were significantly higher in the Cu supplemented group. Mn and Ni significantly decreased and Mo increased in the brain, and Se (diaphragm) decreased in the Cu supplemented group. These interactions are unknown, and possibly with more than two metals involved as suggested in the case of the ratio Se:Cu in the animals of this study. The possible role of Cu supplementation on the status of certain metals associated to neurological diseases (Mn-Ni) in the brain deserves further investigation. Finally new research on Cu-Se supplementation is necessary to better understand the risk of the animals to suffer from Se deficiency.
      409Scopus© Citations 12
  • Publication
    Developing seaweed/macroalgae as feed for pigs
    Macroalgae are a promising source of nutritional ingredients including proteins, polysaccharides and minerals. The need to increase animal and feed production has increased interest in macroalgae as underutilised resources with promising applications as alternative animal feeds. This chapter summarizes the nutritional attributes of macroalgae in terms of macro and micronutrients as a source of protein and other compounds in pig nutrition. The benefits of macroalgae or macroalgal derived extracts in feed are discussed together with future trends and challenges in the development of effective feed formulations.
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  • Publication
    Trace mineral status and toxic metal accumulation in extensive and intensive pigs in NW Spain
    The aim of the present study was to determine trace element status and toxic metal accumulation in extensive and intensive pigs in NW Spain. Soil, feed and animal tissues (liver, kidney and muscle from 112 pigs) were collected from extensive and intensive pig farms across NW Spain and analysed for metals by ICP-MS and ICP-OES. Our results indicate that animals from both extensive and intensive systems showed an adequate mineral status and that toxic metal residues were generally low, no sample exceeding the maximum admissible levels in meat and meat products established by the EU. Trace element concentrations were generally higher in the intensive pigs possibly reflecting mineral supplementation in the concentrate feed. The statistically significantly higher As, Hg and Pb residues as well as the better Fe and Ni status in extensive pigs could be related at least in part with soil ingestion when rooting. On the contrary, the higher Cd accumulation in the intensive pigs can be explained considering Cu and Zn supplementation in the concentrate feed. Our results also seem to indicate that toxic metal accumulation as well as trace element status in different tissues could be related to metabolic aspects (i.e. related to breed and growth rate) as well as certain management practices (i.e. physical exercise when grazing).
    Scopus© Citations 27  203
  • Publication
    Seasonal Variation of the Proximate Composition, Mineral Content, Fatty Acid Profiles and Other Phytochemical Constituents of Selected Brown Macroalgae
    The main objective was to determine the chemical, phytochemical, fatty acid and mineral profiles of three commercially relevant brown macroalgae (Laminaria digitata, Laminaria hyperborea and Ascophyllum nodosum) collected each season for two years off the west coast of Ireland. All the chemical, phytochemical, fatty acid and minerals analysed varied significantly depending on the macroalgal species, season and year of collection. Overall, the protein contents of macroalgae were negatively correlated with carbohydrate content. Protein (2–11%) was at its highest during winter and/or spring, decreasing to a minimum during summer and/or autumn. The three macroalgal species analysed in this study had clearly differentiated fatty acid profiles. The concentration of fatty acids was higher in A. nodosum compared with both Laminaria species. The mineral profile of the three macroalgal species was rich in essential metals, particularly Ca, Mg and P, while the levels of I were approximately 9- to 10-fold higher in both Laminaria spp. compared with A. nodosum. The levels of toxic metals (Cd, Hg and Pb) in all the macroalgal species studied were low in the current study; while the levels of total As were high (49–64 mg/kg DW macroalgae) compared with previous reports.
      289Scopus© Citations 31
  • Publication
    New Breeding Strategies in Organic Dairy Farming
    The selection of an appropriate breed in dairy farms will have a huge influence on the animals’ welfare and production. This is especially noticeable in animal production systems that aim to maximize the use of on-farm resources (low-input production), i.e., organic farms. The animal production in organic farming systems focuses on maximizing the utilization of forage and improving the animals’ health and welfare, while reducing the application of drugs routinely applied in the treatment and prevention of diseases in the conventional farms. Thus, the selection of animals adapted to these harsh farming conditions is essential for the success of an organic farm. However, the current animal breeding strategies adopted by the farmers do not differ between the intensive and the organic animal production systems; i.e., the Holstein-Friesian is the most commonly used breed in the organic and intensive dairy farms, despite the poor production and adaptability of these animals to the organic production systems. Recent studies showed that animals bred to produce high milk yields in the conventional systems are not capable to adapt to pasture-based systems. Cattle breeding strategies based on the selection of the animals for functional traits, or the efficiency of the cows to use scarce resources (inputs), could be a good strategy when selecting animals for organic farms. This chapter analyzes the animal breeding strategies currently performed in the organic farms, and discusses the novel strategies and animal breeds that could potentially benefit different organic dairy farming systems, including multifunctional farms.
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  • Publication
    The interlobular distribution of copper in the liver of beef calves on a high-copper diet
    The aims of the present study were 1) to evaluate the interlobular distribution of copper (Cu) in the liver of beef calves on a high-Cu diet, 2) to determine whether this distribution differs between Galician Blonds and Holstein Friesians, and 3) to determine whether in vivo needle biopsy provides an appropriate measure of overall hepatic Cu status. Liver biopsies were performed before slaughter on twenty-nine 10-month-old beef calves fed growing and finishing diets supplemented with 35 mg/kg of Cu sulfate (10 Galician Blonds, 9 Holstein Friesians, and 10 Galician Blond × Holstein Friesian crosses). At slaughter, samples taken from 6 regions of the liver (the internal and external faces of the right lobe; the left, caudate, and quadrate lobes; and the processus papillaris) were acid digested, and their Cu contents were determined by inductively coupled plasma atomic emission spectrometry. The highest Cu concentrations were found in the left lobe, followed by the processus papillaris, and the lowest Cu concentrations were found in the caudate and quadrate lobes. Different breeds differ in absolute hepatic Cu levels, but interlobular Cu distribution does not appear to depend on breed, at least when Galician Blonds are compared with Holstein Friesians. In vivo needle biopsy afforded accurate estimates of overall hepatic Cu status.
    Scopus© Citations 16  279
  • Publication
    Essential and toxic trace element concentrations in different commercial veal cuts in Spain
    The aim of this study was to evaluate essential and toxic element concentration of ten commercially available veal cuts, together with diaphragm, cardiac muscle and liver tissue from 10 animals of 'Galician Supreme Veal'. Essential trace elements (Co, Cr, Cu, Fe, Mn, Mo, Ni, Se and Zn) and toxic elements (As, Cd, Hg and Pb) were determined by ICP-MS. Essential trace element concentrations ranged from 0.002–55.64 mg/kg between muscles. Toxic element concentrations were very low, and high numbers of samples showed unquantifiable residues of Cd and Pb. Veal cuts including muscles with a high proportion of oxidative slow-twitch fibers (diaphragm and cardiac muscle) showed significantly higher essential trace element concentrations, the lower concentrations being found in veal cuts including glycolytic fast-twitch fibers (eye round). Our results suggest that essential and toxic trace element concentration could be used as a new meat quality parameter, or to add further value to certain products (i.e. livestock reared on extensive systems with high physical activity).
      502Scopus© Citations 30
  • Publication
    Effect of type of muscle and Cu supplementation on trace element concentrations in cattle meat
    Considering that meat is an important source of metals exposure to humans it is important to explore trace element concentrations in different types of muscles. Because of the demonstrated effect of Cu-supplementation on mineral status, the influence of Cu-supplementation was also evaluated. Samples of four different muscles (diaphragm, cardiac, semitendinous and pectoral, n=120) from beef calves receiving typical commercial diets Cu-supplemented (15mg Cu2SO4/kg DM) and non-supplemented were taken and acid digested. The levels of non-essential (As, Cd, Hg, Pb and Sn) and essential (Co, Cr, Fe, Mn, Mo, Ni, Se and Zn) elements were analyzed by ICP-MS. The statistical analyzes included two way Anova, post hoc DHS Tukey and Spearman correlations. The most active and less fat containing muscles showed in general the highest essential and the lowest non-essential trace element accumulation. As and Hg muscular residues are indicative of animal exposure, however, in situations of an adequate mineral status, essential trace element concentrations in muscle are irrespective of the mineral status of the animal and could be possibly related to their own particular muscular metabolism. Cu-supplementation significantly reduced As but caused a significant decrease of Se, which could have significance for the animal's health.
    Scopus© Citations 34  287
  • Publication
    The involvement of metallothionein in hepatic and renal Cd, Cu and Zn accumulation in pigs
    This study investigated the involvement of metallothionein (MT) in hepatic and renal cadmium (Cd) accumulation and the interactions of this element with the essential elements copper (Cu) and zinc (Zn) in pigs receiving diets with or without Cu and Zn supplementation, in intensive and extensive production systems respectively. Animals from intensive systems showed significantly higher Cd concentrations in the liver (83.3 μg/kg wet weight) and kidney (343 μg/kg) than animals from extensive systems (33.2 and 130 μg/kg respectively). Cu (liver 16.9, kidney 5.52. mg/kg) and Zn (82.8 and 29.7. mg/kg) concentrations were also significantly higher in pigs from intensive than in animals from extensive systems (Cu 10.1 and 4.64. mg/kg, Zn 66.2 and 23.1. mg/kg). Pigs from intensive systems showed 50% higher kidney MT concentrations than animals from extensive systems (278 and 183. mg/kg respectively), whereas liver MT concentrations were very similar in the two groups (1696 and 1517. mg/kg respectively). MT concentrations in both the liver and the kidney were strongly dependent on the Zn status of the animal. In the liver neither Cu nor Cd displaced Zn from MT, and the proportion of MT binding sites apparently occupied by Cu and Cd decreased with increasing hepatic MT concentration, despite the fact that both Cu and Cd have higher affinity for MT than Zn. The proportion of MT binding sites occupied by Cu and Cd was also directly related to Zn:Cu ratio in hepatic cells. In the kidney, in contrast, Cu seems able to compete with Zn for MT binding sites, and the proportion of MT binding sites occupied by Cu increased with increasing renal MT concentration. © 2012 Elsevier B.V.
    Scopus© Citations 9  236