Now showing 1 - 10 of 18
  • 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.
  • 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.
  • 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.
  • 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.
  • Publication
    Histochemistry evaluation of the oxidative stress and the antioxidant status in Cu-supplemented cattle
    The aim of this paper is to evaluate at a histopathological level the effect of the most commonly used copper (Cu) supplementation (15 mg/kg dry matter (DM)) in the liver of intensively reared beef cattle. This was done by a histochemistry evaluation of (i) the antioxidant capacity in the liver - by the determination of metallothioneins (MT) and superoxide dismutase (SOD) expression - as well as (ii) the possible induction of oxidative damage - by the determination of inducible nitric oxide synthase (iNOS), nitrotyrosine (NITT), malondialdehyde (MDA) and 8-oxoguanine (8-oxo) - that (iii) could increase apoptotic cell death - determined by cytochrome-c (cyto-c), caspase 1 (casp1) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL). Liver samples from Cu-supplemented (15 mg Cu sulphate/kg DM, n = 5) and non-supplemented calves (n = 5) that form part of other experiments to evaluate Cu status were collected at slaughter and processed for immunohistochemistry and TUNEL. MT expression was diffuse and SOD showed slight changes although without statistical significance. iNOS and NITT positive (+) cells significantly increased, mainly around the central veins in the animals from the Cu-supplemented group, whereas no differences were appreciated for the rest of the oxidative stress and apoptosis markers. Under the conditions of this study, which are the conditions of the cattle raised in intensive systems in NW Spain and also many European countries, routinely Cu supplementation increased the risk of the animals to undergo subclinical Cu toxicity, with no significant changes in the Cu storage capacity and the antioxidant defensive system evaluated by MT and SOD expression, but with a significant and important increase of oxidative damage measured by iNOS and NITT. The results of this study indicated that iNOS and NITT could be used as early markers of initial pathological changes in the liver caused by Cu supplementation in cattle, although more studies in cattle under different levels of Cu supplementation are needed.
      218Scopus© Citations 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.
  • 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).
      541Scopus© Citations 32
  • 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  413
  • 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 80  318
  • 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  252