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Pedigree analysis of eight Spanish beef cattle breeds

  • Gutiérrez, J. P.
  • Altarriba, J.
  • Díaz, C.
  • Quintanilla, R.
  • Cañón, J.
  • Piedrafita, J.
The genetic structure of eight Spanish autochthonous populations (breeds) of beef cattle were studied from pedigree records. The populations studied were Alistana and Sayaguesa (minority breeds), Avileña - Negra Ibérica and Morucha ("dehesa" breeds, with a scarce incidence of artificial insemination), and mountain breeds, including Asturiana de los Valles, Asturiana de la Montaña and Pirenaica, with extensive use of AI. The Bruna dels Pirineus breed possesses characteristics which make its classification into one of the former groups difficult. There was a large variation between breeds both in the census and the number of herds. Generation intervals ranged from 3.7 to 5.5 years, tending to be longer as the population size was larger. The effective numbers of herds suggest that a small number of herds behaves as a selection nucleus for the rest of the breed. The complete generation equivalent has also been greatly variable, although in general scarce, with the exception of the Pirenaica breed, with a mean of 3.8. Inbreeding effective population sizes were actually small (21 to 127), especially in the mountain-type breeds. However, the average relatedness computed for these breeds suggests that a slight exchange of animals between herds will lead to a much more favourable evolution of inbreeding. The effective number of founders and ancestors were also variable among breeds, although in general the breeds behaved as if they were founded by a small number of animals (25 to 163).

Reconstructing forest history from archaeological data A case study in the Duero basin assessing the origin of controversial forests and the loss of tree populations of great biogeographical interest

  • Hernández, L.
  • Rubiales, J. M.
  • Morales-Molino, C.
  • Romero, F.
  • Sanz, C.
  • Gómez Manzaneque, F.
The study of more than 700 charcoals from the Vaccaean settlement of Pintia (Padilla del Duero, Valladolid) provides new local and detailed data about the Iron Age II forest composition in Continental-Mediterranean inland Spain. Pinus gr. sylvestris/. nigra (from which an unexpectedly high number of charcoals were identified), together with Mediterranean pines (also highly represented), Juniperus L.;evergreen and deciduous Quercus, were the main taxa living in the area, revealing two different marked biogeographical elements in the late-Holocene landscapes of the Duero basin Mediterranean and Eurosiberian. On one hand, the results shed new light on the assessment of the origin of Mediterranean pinewoods in the area. On the other hand, the charcoal assemblage of Pintia reveals a more important presence of the current Mediterranean highland pines in the lowlands of the Central Iberian Peninsula in the late-Holocene suggesting the existence of interglacial refugia. Finally, this work highlights palaeoecological studies as valuable tools to support decisions on forest management related to conservation and restoration of our natural heritage. © 2011 Elsevier B.V.

A featured-based strategy for stereovision matching in sensors with fish-eye lenses for forest environments

  • Herrera, P. J.
  • Pajares, G.
  • Guijarro, M.
  • Ruz, J. J.
  • Cruz, J. M.
  • Montes, F.
This paper describes a novel feature-based stereovision matching process based on a pair of omnidirectional images in forest stands acquired with a stereovision sensor equipped with fish-eye lenses. The stereo analysis problem consists of the following steps image acquisition, camera modelling, feature extraction, image matching and depth determination. Once the depths of significant points on the trees are obtained, the growing stock volume can be estimated by considering the geometrical camera modelling, which is the final goal. The key steps are feature extraction and image matching. This paper is devoted solely to these two steps. At a first stage a segmentation process extracts the trunks, which are the regions used as features, where each feature is identified through a set of attributes of properties useful for matching. In the second step the features are matched based on the application of the following four well known matching constraints, epipolar, similarity, ordering and uniqueness. The combination of the segmentation and matching processes for this specific kind of sensors make the main contribution of the paper. The method is tested with satisfactory results and compared against the human expert criterion. © 2009 by the authors.

Short-term effects of poultry litter application on silage maize yield and soil chemical properties

  • Hirzel, J.
  • Undurraga, P.
  • Novoa, F.
  • Walter, I.
If properly managed, poultry litter (PL) might be a good alternative to conventional fertilizers. This paper reports on a three-year field study to compare the effects of two consecutive PL and traditional mineral fertilizer applications on silage maize (Zea mays) production and soil chemical properties. The experiment was undertaken on volcanic soil in the Central-South Region of Chile. The PL was applied at doses of 10, 15 and 20 Mg ha−1, with and without mineral fertilizer to 50 m2 plots, and the outcomes compared with those obtained with two rates of nitrogen mineral fertilizer equivalent to the mid and high PL rates. Maize yield showed a positive response to all treatments, although the mean yield obtained with the PL treatments was higher than with the mineral fertilizer in the third year, in which no fertilizers were applied. The whole plant N concentration of the PL plants was significantly higher than that of the plants that received mineral fertilizer (this was the only nutrient variable for which such differences were found), but the values were not related to the amount of PL applied. After two annual applications of PL, slight increases in soil-available inorganic N and P were observed. However, the values obtained were low, highlighting the high P fixation capacity of the soil as well as its high capacity to stabilise organic matter. No other soil variables studied were significantly affected by any of the treatments. © 2009 by The JG Press, Inc. All rights reserved.

Further characterisation of transmissible spongiform encephalopathy phenotypes after inoculation of cattle with two temporally separated sources of sheep scrapie from Great Britain Veterinary Research

  • Konold, T.
  • Nonno, R.
  • Spiropoulos, J.
  • Chaplin, M. J.
  • Stack, M. J.
  • Hawkins, S. A. C.
  • Cawthraw, S.
  • Wilesmith, J. W.
  • Wells, G. A. H.
  • Agrimi, U.
  • Di Bari, M. A.
  • Andreóletti, O.
  • Espinosa, J. C.
  • Aguilar-Calvo, P.
  • Torres, J. M.
Background The infectious agent responsible for the bovine spongiform encephalopathy (BSE) epidemic in Great Britain is a transmissible spongiform encephalopathy (TSE) strain with uniform properties but the origin of this strain remains unknown. Based on the hypothesis that classical BSE may have been caused by a TSE strain present in sheep, cattle were inoculated intracerebrally with two different pools of brains from scrapie-affected sheep sourced prior to and during the BSE epidemic to investigate resulting disease phenotypes and characterise their causal agents by transmission to rodents. Results As reported in 2006, intracerebral inoculation of cattle with pre-1975 and post-1990 scrapie brain pools produced two distinct disease phenotypes, which were unlike classical BSE. Subsequent to that report none of the remaining cattle, culled at 10 years post inoculation, developed a TSE. Retrospective Western immunoblot examination of the brains from TSE cases inoculated with the pre-1975 scrapie pool revealed a molecular profile similar to L-type BSE. The inoculation of transgenic mice expressing the bovine, ovine, porcine, murine or human prion protein gene and bank voles with brains from scrapie-affected cattle did not detect classical or atypical BSE strains but identified two previously characterised scrapie strains of sheep. Conclusions Characterisation of the causal agents of disease resulting from exposure of cattle to naturally occurring scrapie agents sourced in Great Britain did not reveal evidence of classical or atypical BSE, but did identify two distinct previously recognised strains of scrapie. Although scrapie was still recognizable upon cattle passage there were irreconcilable discrepancies between the results of biological strain typing approaches and molecular profiling methods, suggesting that the latter may not be appropriate for the identification and differentiation of atypical, particularly L-type, BSE agents from cattle experimentally infected with a potential mixture of classical scrapie strains from sheep sources. © 2015 Crown.

Production, survival, and evaluation of solid-substrate inocula of Penicillium oxalicum, a biocontrol agent against Fusarium wilt of tomato

  • Larena, I.
  • Melgarejo, P.
  • De Cal, A.
Production of conidia of Penicillium oxalicum (ATCC number pending), a biocontrol agent of Fusarium oxysporum f. sp. lycopersici, was tested in liquid and solid fermentation. P. oxalicum produced 250-fold more conidia in solid than in liquid fermentation at 30 days after inoculation of substrate. Solid fermentation was carried out in plastic bags (600 cm3) especially designed for solid fermentation (VALMIC) containing 50 g of peat/vermiculite (PV) (11, wt/wt) with 40% moisture, sealed, sterilized, and then inoculated with 1 ml of a conidial suspension of P. oxalicum (105 conidia g-1 dry substrate), sealed again, and incubated in darkness at 20 to 25°C for 30 days. Addition of amendments to PV in a proportion of 0.5 (wt/wt) significantly increased conidial production of P. oxalicum. The best production was obtained on PV plus meal of cereal grains (barley) or leguminous seeds (lentil) (100-fold higher). Conidial production obtained after 5 days of inoculation was similar to that obtained at 30 days. However, viability of conidia produced in PV plus lentil meal was 35% higher than that of conidia produced in PV plus barley meal. Changes in proportions (110.5, wt/wt/wt; 111, wt/wt/wt; 10.50,5, wt/wt/wt; 1:1:0.5, vol/vol/vol) of components of the substrate (peat/vermiculite/lentil meal) did not enhance production or viability of conidia. Optimal initial moisture in the substrate was 30 to 40%. At lower moistures, significant reductions of production of conidia were observed, particularly at 10%. There was a general decline in the number of conidia in bags with time of storage at -80, -20, 4, and 25°C, or at room temperature (range from 30 to 15°C), with the highest decline occurring from 60 to 180 days. Conidial viability also was reduced with time, except for conidia stored at -20°C. Fresh conidia produced in solid fermentation system or those conidia stored at -20°C for 180 days reduced Fusarium wilt of tomato by 49 and 61%, respectively.

Species coexistence in a mixed Mediterranean pine forest Spatio-temporal variability in trade-offs between facilitation and competition

  • Ledo, A.
  • Cañellas, I.
  • Barbeito, I.
  • Gordo, F. J.
  • Calama, R. A.
  • Gea-Izquierdo, G.
Studying species coexistence is key to understanding the way in which forests will respond to climate change. We studied the patterns of mixed stands including two main Mediterranean pine species Pinus pinaster Ait.;Pinus pinea L. The spatial distribution of adult trees and saplings was studied via a point pattern approach. The effect of competition on growth of adult trees was investigated by comparing the performance of several competition indexes for each pine species through generalized linear models. Adult trees formed mixed clumps in which individuals of both species appeared together. Part of the tree growth variation was explained by tree size along with tree competition. However, the effect of conspecific vs heterospecific competition on tree growth differed and reflected species-specific neighbor-asymmetric competition. Facilitation was fundamental in the early stages for tree species development. The spatial distribution of saplings was strongly related to the spatial distribution of adult trees, also being asymmetrically clustered and neighbor-species-dependent. However, the required facilitation in early life-stage trees shifted to competition among trees in the adult stage. Species mixture may be desirable in terms of increasing and diversifying productivity, although the conditions currently present in the stand are likely to lead to future dominance of P. pinea over P. pinaster due not only to the greater competition tolerance of the former but also to a greater ability to successfully recruit in the plots, forming clusters that may be in turn be impenetrable to P. pinaster. Therefore, in order to maintain mixed stands, it would be necessary to enforce adequate silvicultural management strategies which avoid future stand dominance by P. pinea. © 2014 Elsevier B.V.

Toxicological characterisation of sludge from sewage treatment plants using toxicity identification evaluation protocols based on in vitro toxicity tests

  • Babín, M. M.
  • García, P.
  • Fernández, C.
  • Alonso, C.
  • Carbonell, G.
  • Tarazona, J. V.
The ecotoxicological characterisation of complex mixtures, such as sludge from sewage treatment plants, is complex. Toxicity identification evaluation (TIE) protocols, developed by the United States Environmental Protection Agency (US EPA); to identify toxic pollutants in complex effluents, are useful tools in this context; to solve the difficulties in assessing unknown organic pollutants by analytical methods, the usefulness of bioassays to detect the relevant (toxic) organic compounds present in complex samples, and the possibilities of in vitro cytotoxicity tests as screening tools, offers a profitable combination. The sludge obtained from a sewage treatment plant was extracted by acetonitrile using a microwave extractor and fractionated in an HPLC system. The toxicity of every fraction was assayed using a RTG-2 cytotoxicty test, based on the fibroblastic RTG-2 fish cell line (ATCC, CCL N. 55). At exponential growth, three endpoints, β-galactosidase activity, culture viability assayed by the neutral red assay (NR) and inhibition of growth rate using the FRAME KB protein assay (KBP), were used. By plotting the toxicity of each fraction vs elution time, the corresponding "toxicograms" were built. The UV and fluorescence chromatograms are compared to the three toxicograms (one for each toxicity endpoint). © 2001 Elsevier Science Ltd. All rights reserved.

Effects of a single injection of LHRH on the response of anestrous ewes to the introduction of rams

  • Lopez-Sebastian, A.
  • Gomez-Brunet, A.
  • Inskeep, E. K.
Two methods of induction of ovulation were examined in Manchega ewes that were in postpartum anestrus during the nonbreeding season. The experiment was of 2 X 2 X 3 factorial design. The methods compared were introduction of rams and this treatment plus an im injection of 50 micrograms luteinizing hormone releasing hormone (LHRH) at the time rams were introduced. Variations in response due to month of treatment (April, May or June) and interval from lambing to treatment (1, 2 or 3 mo) and their interactions with type of treatment were examined. Responses studied were proportions of ewes showing increases in plasma progesterone at (a) 10 d or (b) 17 or 24 d post-treatment, or lambing by 200 d post-treatment, and interval from treatment to lambing for ewes that did lamb by 200 d. The formation of a corpus luteum was determined by concentrations of progesterone in plasma; a positive response was considered to be a concentration greater than .5 ng/ml (baseline values averaged .1 ng/ml). Overall, there was no benefit of LHRH above the response to introduction of males only, in any trait examined. There was a significant interaction of treatment with month of treatment on the proportion of ewes forming corpora lutea by 17 or 24 d after initiation of treatment. This proportion was lower in June (38 vs 66% in April and 82% in May) for ewes receiving LHRH, but did not differ among months (61 to 68%) for ewes exposed to males only.(ABSTRACT TRUNCATED AT 250 WORDS)

Ultra-sensitive detection of two garlic potyviruses using a real-time fluorescent (Taqman®) RT-PCR assay

  • Lunello, P.
  • Mansilla, C.
  • Conci, V.
  • Ponz, F.
A method for the detection of Onion yellow dwarf virus (OYDV) and Leek yellow stripe virus (LYSV), the two most prevalent garlic potyviruses, has been developed that combines IC-RT-PCR/RT-PCR with the use of TaqMan® probes. Comparisons with ELISA results obtained with identical OYDV and LYSV infected samples showed sensitivity in detecting these viruses increased up to 106-fold. OYDV and LYSV were detected using different fluorochromes in the probe, thus allowing unequivocal diagnosis for each of them. The polyvalence of the designed virus-specific primers and probes was shown through their application to the detection of three isolates from very different geographical areas and from different hosts. A second version of the method avoids the need for an immunocapture step through the performance of a TaqMan® RT-PCR assay directly on extracts of garlic cloves. This modification on the proposed basic method allows the analysis of bulb samples in 3-4 h but did not give reproducible results with leaves. Both versions of the new diagnostic method bear great potential for their implementation in virus-free certification schemes in garlic, a vegetatively propagated crop for which such a certification is critical for a high-quality product. © 2004 Elsevier B.V. All rights reserved.

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