Now showing 1 - 10 of 18
  • Publication
    Toxic and essential metals in liver, kidney and muscle of pigs at slaughter in Galicia, north-west Spain
    The aims of the study were to evaluate toxic and essential metal concentrations in meat and offal from pigs in north-west Spain to compare these with reported metal concentrations in pigs in other countries and in cattle in this region, and to relate the observed concentrations to maximum acceptable concentrations. Samples from 63 pigs aged 6 months were randomly collected at slaughter. After acid digestion, levels of metals were determined by ICP-OES and ICP-MS. As regards the toxic metals, mean concentrations in liver, kidney and muscle were 0.073, 0.308 and 0.009 mg kg-1 fresh weight for cadmium, 0.004, 0.008 and 0.003 mg kg-1 for lead, 0.013, 0.011 and 0.003 mg kg-1 for arsenic, and 0.001, 0.002 and 0.001 mg kg-1 for mercury. These concentrations can be considered low, and in general similar to those reported in similar studies in recent years. In addition, maximum admissible concentrations established by the European Union were not exceeded in any sample. As regards the essential metals, concentrations in liver, kidney and muscle were 14.9, 5.63 and 6.85 mg kg-1 for copper, 81.3, 28.9 and 42.5 mg kg-1 for zinc, 195, 51.6 and 26.5 mg kg-1 for iron; 1.17, 2.51 and 0.656 mg kg-1 for selenium, 3.32, 1.56 and 1.01 mg kg-1 for manganese, 0.023, 0.027 and 0.003 mg kg-1 for cobalt, 0.120, 0.077 and 0.131 mg kg-1 for chromium, 0.009, 0.027 and 0.026 mg kg-1 for nickel, and 1.62, 0.683 and 0.140 mg kg-1 for molybdenum. These concentrations are all within the accepted adequate-safe ranges for this animal species, and in general are in line with those previously reported in the literature.
    Scopus© Citations 77  303
  • Publication
    Influence of breed on blood and tissue copper status in growing and finishing steers fed diets supplemented with copper
    To evaluate the influence of breed on the accumulation of dietary copper (Cu) in tissue, and on blood parameters indicative of Cu status, ten Galician Blond, nine Holstein-Friesian and ten Galician Blond × Holstein-Friesian cross (GB × HF) steers were fed diets supplemented with 35 mg/kg DM of CuSO4 during their growing and finishing periods. Blood samples were taken monthly, and samples of liver, kidney, brain, heart, spleen and muscle were taken at slaughter. Cu concentrations were determined by ICP-AES. Holstein-Friesian calves had significantly higher total liver Cu contents than Galician Blonds and GB × HF crosses (mean 1070, 663 and 868 mg, respectively), combined with higher hepatic Cu concentrations (174, 140 and 166 mg/kg wet weight, respectively). Holstein-Friesian calves had also the highest prevalence (89%) of hepatic Cu concentrations exceeding the toxic limit of 150 mg/kg wet weight. Breed did not have a statistically significant influence on blood parameters. With the exception of the semitendinosus muscle, where Holstein-Friesians (0.790 mg/kg) had significantly higher Cu levels than Galician Blonds (0.541 mg/kg) or GB × HF crosses (0.631 mg/kg), no other statistically significant differences by breed in the extrahepatic tissue Cu distribution were observed. A negative statistical association between carcass performance and the ratio of semitendinosus and liver Cu concentration could indicate that the animals with a better carcass performance (Galician Blonds) could need a higher Cu mobilisation into the muscle, resulting in a lower hepatic storage.
    Scopus© Citations 15  397
  • 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.
      407Scopus© Citations 12
  • 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  276
  • 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
    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
    Relationship between the essential and toxic element concentrations and the proximate composition of different commercial and internal cuts of young beef
    This paper seeks to evaluate the relationship between the trace element concentrations and the proximate composition of different cuts of young beef to provide helpful information to consumers in the selection of meat that could fit different nutritional requirements. Ten commercially cuts of young beef (rib boneless entrecote, tenderloin, eye round, thick flank, tail of rump, chuck tender, shin, upper chuck, flank and brisket) together with two internal muscles (diaphragm and cardiac muscle) from ten male Galician blonde calves aged approximately 9 months at slaughter and a carcass weight of 242 ± 2 kg were analyzed. A strong negative association between the main essential trace elements (Co, Cu, Fe, Mn and Se) and the protein concentration of the muscles was found, which could be related to the variable predominance of slow- or fast-twitch fibers in the different muscles. Since trace mineral concentrations in muscle are partly genetically determined and related to palatability traits, understanding the relationships between the trace element concentrations and the proximate composition could be a valuable tool for selective breeding of beef to improve the nutritional value of meat.
    Scopus© Citations 9  74
  • 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 33  280
  • Publication
    Trace metal exposure in different livestock production systems
    Industrial and agricultural activities are associated with environmental pollution as these practices contribute to increase further the concentration of minerals derived from the parent rock, present naturally in the soil. Heavy metals (i.e., arsenic, cadmium, lead and mercury) and excessive levels of essential metals (such as copper and zinc) have negative effects on the health of both animals and humans. The exposure of animals to toxic elements or excessive levels of essential minerals could influence greatly the mineral content of different animal derived products for human consumption (i.e., meat, offal and milk) and may affect significantly human health. The exposure of livestock to different minerals varies depending on the animal husbandry practices adopted by the farmers, such as the use of mineral supplements in animals’ feed and the foraging practices of the farm (i.e., grazing, type of soil and forage contamination). This chapter focuses on the influence of different farming practices on the exposure of livestock to toxic and trace elements, emphasising the differences between the intensive and organic farming systems. The relationship between different farming practices and the mineral content of animal derived products, together with the implications of these farming practices for the consumers and environment are also discussed.
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  • Publication
    Assessment of the functional properties of protein extracted from the brown seaweed Himanthalia elongata (Linnaeus) S. F. Gray
    A protein extract from the brown seaweed Himanthalia elongata (Linnaeus) S. F. Gray was prepared and its functional properties, colour and amino acid composition were assessed for its potential future use by the food industry. The total content of amino acids was determined as 54.02 ± 0.46 g amino acids/kg dry weight, with high levels of the essential amino acids lysine and methionine. SDS-PAGE showed 5 protein bands with molecular weights of 71.6, 53.7, 43.3, 36.4 and 27.1 kDa. The water holding capacity and oil holding capacity were determined as 10.27 ± 0.09 g H2O/g and 8.1 ± 0.07 g oil/g respectively. Foaming activity and stability were higher at alkaline pH values. The emulsifying capacity and stability of the extract varied depending on the pH and oil used. These results demonstrate the potential use of Himanthalia elongata protein extract in the food industry.
    Scopus© Citations 86  1431