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Miranda, Marta
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Miranda, Marta
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Miranda, Marta
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Now showing 1 - 10 of 17
- PublicationInfluence 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.20 - PublicationNew Breeding Strategies in Organic Dairy Farming(Nova Science, 2018-01)
; ; ; ; 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.217 - PublicationEvaluation of the need of copper supplementation in intensively reared beef cattle(Elsevier, 2011-05)
; ; ; ; 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.283Scopus© Citations 18 - PublicationSeasonal Variation of the Proximate Composition, Mineral Content, Fatty Acid Profiles and Other Phytochemical Constituents of Selected Brown Macroalgae(MDPI, 2021-04-04)
; ; ; ; ; 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.141Scopus© Citations 16 - PublicationRelationship between the essential and toxic element concentrations and the proximate composition of different commercial and internal cuts of young beef(Springer, 2017-04-10)
; ; ; ; 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.35Scopus© Citations 6 - PublicationInfluence of Cu supplementation on toxic and essential trace element status in intensive reared beef cattle(Elsevier, 2011-12)
; ; ; ; ; 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.343Scopus© Citations 11 - PublicationDeveloping seaweed/macroalgae as feed for pigsMacroalgae 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.
97 - PublicationEffect of type of muscle and Cu supplementation on trace element concentrations in cattle meat(Elsevier, 2011-06)
; ; ; ; 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.205Scopus© Citations 32 - PublicationTrace metal exposure in different livestock production systems(Nova Science, 2018-09)
; ; ; ; 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.80 - PublicationMacroalgae for Functional Feed Development: Applications in Aquaculture, Ruminant and Swine Feed IndustriesPlant 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.
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