Now showing 1 - 10 of 17
  • 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.
      45
  • 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.
      244
  • Publication
    Macroalgae for Functional Feed Development: Applications in Aquaculture, Ruminant and Swine Feed Industries
    Plant and animal derived products are the main ingredients currently used by the feed industry to produce concentrate feed. There is a need of novel feed ingredients to meet the demand of high quality products by the aquaculture, ruminant and swine production systems, together with the challenge of implementing new sustainable and environmentally friendly processes and ingredients demanded by the modern society. Macroalgae are a large and diverse group of marine organisms that are able to produce a wide range of compounds with unique biological properties. This chapter discusses the incorporation of macroalgae or macroalgal derived ingredients as a source of both macro-nutrients (i.e., proteins, polysaccharides and fatty acids) and micro-nutrients (i.e., minerals and pigments) for animal feed production. The biological health benefits of the macroalgal ingredients beyond basic nutrition for the development of functional feed in the aquaculture, the ruminant and the swine sectors are also discussed together with the industrial challenges of its application.
      1386
  • Publication
    Evaluation of the need of copper supplementation in intensively reared beef cattle
    The aim of this investigation was to evaluate whether, in the nutritional management of commercial feedlots of NW Spain based mainly on concentrate feed from international raw materials, copper (Cu) supplementation is justified to maintain the physiological requirements. This was done by evaluating blood Cu parameters (serum Cu, whole blood Cu and serum caeruloplasmin), haematological (red blood cells, microhematocrit, haemoglobin, white blood cells, and thrombocytes), productive parameters (initial and final live weight, feed intake, average daily gain, carcass weight and performance and internal organs weight) and organic Cu accumulation at slaughter (liver, kidney, muscle, spleen and brain) in intensive beef cattle that received a standard diet with 15. mg/kg of Cu sulphate (Cu supplemented group, n = 10) and without Cu (non-supplemented group, n = 10) during all the productive cycle (growing and finishing periods and animals aged 12 to 36. weeks). In general Cu supplementation did not statistically affect blood Cu indicators, productive and haematologic parameters, and the levels of these parameters were within their normal ranges during the whole study. There were significant statistic differences in tissue Cu accumulation, mainly in the liver, with 90% of the animals of the Cu supplemented group showing hepatic Cu levels exceeding the adequate range and 50% within the concentrations associated with Cu toxicity. Under the conditions of this study, which are the conditions of the cattle raised under intensive methods in many European countries, routinely Cu supplementation is not justified to maintain an adequate Cu status in the animals or to improve productive parameters. More information about the risk of presence of Cu antagonists in the concentrate diets should be necessary to justify routinely Cu supplementation in intensively reared beef cattle.
      345Scopus© Citations 20
  • 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  400
  • 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
    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.
      283Scopus© Citations 31
  • 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
    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.
      358
  • 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