Options
Miranda, Marta
Preferred name
Miranda, Marta
Official Name
Miranda, Marta
Research Output
Now showing 1 - 7 of 7
- 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.358 - 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.Scopus© Citations 34 287 - PublicationInfluence of breed on blood and tissue copper status in growing and finishing steers fed diets supplemented with copper(Taylor & Francis, 2010-03-31)
; ; ; ; ; 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 - 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.409Scopus© Citations 12 - PublicationThe interlobular distribution of copper in the liver of beef calves on a high-copper diet(Sage, 2010-03-01)
; ; ; ; ; 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 16 278 - 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.Scopus© Citations 9 76 - PublicationHistochemistry evaluation of the oxidative stress and the antioxidant status in Cu-supplemented cattle(Cambridge University Press, 2012-09)
; ; ; 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.193Scopus© Citations 17