2,269 research outputs found

    The knowledge of zoonotic diseases in swine producers, veterinarians and swine industry allied personnel in Ontario, Canada

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    More than 70% of swine marketed in Canada come from the Canadian Quality Assurance (QGA®) program, established in 1998 with the main purpose of demonstrating the implementation of on-farm good production practices (GPP)

    Improved FPT algorithms for weighted independent set in bull-free graphs

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    Very recently, Thomass\'e, Trotignon and Vuskovic [WG 2014] have given an FPT algorithm for Weighted Independent Set in bull-free graphs parameterized by the weight of the solution, running in time 2O(k5)n92^{O(k^5)} \cdot n^9. In this article we improve this running time to 2O(k2)n72^{O(k^2)} \cdot n^7. As a byproduct, we also improve the previous Turing-kernel for this problem from O(k5)O(k^5) to O(k2)O(k^2). Furthermore, for the subclass of bull-free graphs without holes of length at most 2p12p-1 for p3p \geq 3, we speed up the running time to 2O(kk1p1)n72^{O(k \cdot k^{\frac{1}{p-1}})} \cdot n^7. As pp grows, this running time is asymptotically tight in terms of kk, since we prove that for each integer p3p \geq 3, Weighted Independent Set cannot be solved in time 2o(k)nO(1)2^{o(k)} \cdot n^{O(1)} in the class of {bull,C4,,C2p1}\{bull,C_4,\ldots,C_{2p-1}\}-free graphs unless the ETH fails.Comment: 15 page

    Investigating biosecurity risks associated with the delivery of feed to swine farms

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    Introduction Biosecurity protocols reduce the introduction and spread of pathogens among swine farms. For pigs, biosecurity ensures market stability, maintains export opportunities, and controls spread of production and public health diseases. Salmonella, the second most common cause of bacterial foodborne illness, causes gastrointestinal illness. Pigs can be asymptomatic carriers of the bacteria and pork products are a known source of salmonellosis in humans. Salmonella have been isolated from pigs, boots, flies, rodents, bird feces, feed, feed-ingredients, and feed trucks. The objective was to identify management factors to reduce the risk of disease spread among swine farms through feed trucks. Materials and Methods The study was conducted in two phases - the first phase included a series of focus groups and key-informant interviews; discussions held with swine producers and feed company personnel explored the protocols currently in place that reduce the risk of disease spread through the delivery of feed. Participants were asked to identify possible management changes that could further reduce the risk, and to rate these ideas in terms of their effect on disease control, and feasibility based on implementation and economics. This information was used to structure the second phase of the study – a pilot study. The pilot study was conducted over 6 weeks in the winter of 2013, and included 40 feed truck drivers from 3 Ontario feed companies. Truck drivers filled out log sheets as they delivered feed to swine farms, and provided information about the prevalence of the identified biosecurity risks during the day-to-day delivery of feed. Drivers were randomly assigned to be in either the treatment or control groups. Drivers in the control group delivered feed as they normally do. Drivers in the treatment group were: i) asked not to enter the barn unless absolutely necessary, and ii) were provided with re-usable, washable rubber over-shoes and were asked to wear a clean pair at each farm when they felt safe doing so. Chisquared tests were used to compare the usage of clean boots between drivers in the treatment and control groups. In total, 40 drivers from 3 companies, delivering feed to 2202 farms over 6 weeks (in the winter) collected descriptive data on the factors and compared use of different boots. Results The factors followed by the proportion of farms and drivers where the factor was found were found as follows: Most farms were: keeping areas (driveway, feed bin and barnyard) clean of mud and manure (82%), and dead-stock (91%) was appropriately disposed of and not visible to the driver. Some farms had an outbuilding to deliver bagged feed (24%). Other factors that were identified that producers should work on were to provide farm boots and coveralls for the driver if the driver needed to go into the barn, ordering the correct amount of feed to decrease the numbers of deliveries (or frequencies of deliveries) of feed, and notifying feed mill of a disease outbreak on the farm. Feed truck driver factors included wearing a separate pair of clean, disinfected, dried boots (25%) and gloves (50%) at each farm that is visited (even if the driver does not go into the barn, remaining outside the barn (92%); washing the steering wheel (49%), floor mat (77%) and outside of the truck (32%) every 24 hours. From these results, it may be advisable to increase the frequency of washing the truck. Another factor identified was for the driver to know and follow the farm biosecurity protocols. Half of the time, the driver left the feed bill outside barn (54%). Drivers given disinfected rubber boots were more likely to wear these on farms (42%) than plastic disposable boots (4%) (P<0.05). These drivers were also more likely to wear disinfected rubber boots than the control drivers (11%) (P<0.001). Conclusions and Discussion Biosecurity is a responsibility that is shared among all members of the industry. Feed personnel were encouraged to know more about disease transmission. Acknowledgments Canadian Swine Health Board for funding, feed company personnel and producers for participation

    Antibiotikaeinsatz in der Bayerischen Schweinehaltungspraxis ABYS: Antibiotikaeinsatz und Antibiotikaresistenz in ökologischen Betrieben

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    Between 2012 and 2014, ABYS study recorded antibiotic use, detection and resistance data for 23 organic and 35 conventional pig farms. Antibiotic contents of farm-made fertilizers were assessed by LC/MS-MS. Phenotypic antimicrobial resistance was investigated in Escherichia (E.) coli (indicator bacteria); antimicrobial resistance genes of the total bacterial microbiota (sul(II), tet(A), tet(B), tet(M); marker Measured in nUDD (number of animals treated multiplied by treatment days), colistin was the most frequently used antibiotic, in organic farms followed by tylosin, doxycycline and amoxicillin. Antibiotic residues were rarely detected; however, manure contained up to 10^8 antimicrobial resistance genes per gram; concentrations were higher when the antibiotic had been used on farm. In six farms, antimicrobial resistant E. coli were tracked from the moment when pigs were placed on farm. Some isolates carried a broad variety of resistances from the very beginning that were maintained until slaughter, despite the fact that partly no antibiotics were applied during fattening. Approaches for reducing carry-over of antimicrobial resistant bacteria will be discusse

    Persistence of frequently transmitted drug-resistant HIV-1 variants can be explained by high viral replication capacity

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    Background: In approximately 10% of newly diagnosed individuals in Europe, HIV-1 variants harboring transmitted drug resistance mutations (TDRM) are detected. For some TDRM it has been shown that they revert to wild type while other mutations persist in the absence of therapy. To understand the mechanisms explaining persistence we investigated the in vivo evolution of frequently transmitted HIV-1 variants and their impact on in vitro replicative capacity. Results: We selected 31 individuals infected with HIV-1 harboring frequently observed TDRM such as M41L or K103N in reverse transcriptase (RT) or M46L in protease. In all these samples, polymorphisms at non-TDRM positions were present at baseline (median protease: 5, RT: 6). Extensive analysis of viral evolution of protease and RT demonstrated that the majority of TDRM (51/55) persisted for at least a year and even up to eight years in the plasma. D

    The use of thermographic imaging to evaluate therapeutic response in human tumour xenograft models

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    YesNon-invasive methods to monitor tumour growth are an important goal in cancer drug development. Thermographic imaging systems offer potential in this area, since a change in temperature is known to be induced due to changes within the tumour microenvironment. This study demonstrates that this imaging modality can be applied to a broad range of tumour xenografts and also, for the first time, the methodology’s suitability to assess anti-cancer agent efficacy. Mice bearing subcutaneously implanted H460 lung cancer xenografts were treated with a novel vascular disrupting agent, ICT-2552, and the cytotoxin doxorubicin. The effects on tumour temperature were assessed using thermographic imaging over the first 6 hours post-administration and subsequently a further 7 days. For ICT-2552 a significant initial temperature drop was observed, whilst for both agents a significant temperature drop was seen compared to controls over the longer time period. Thus thermographic imaging can detect functional differences (manifesting as temperature reductions) in the tumour response to these anti-cancer agents compared to controls. Importantly, these effects can be detected in the first few hours following treatment and therefore the tumour is observable non-invasively. As discussed, this technique will have considerable 3Rs benefits in terms of reduction and refinement of animal use.University of Bradfor

    Measurement of pion, kaon and proton production in proton-proton collisions at s=7\sqrt{s}=7 TeV

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    The measurement of primary π±\pi^{\pm}, K±^{\pm}, p and p\overline{p} production at mid-rapidity (y<|y| < 0.5) in proton-proton collisions at s=7\sqrt{s} = 7 TeV performed with ALICE (A Large Ion Collider Experiment) at the Large Hadron Collider (LHC) is reported. Particle identification is performed using the specific ionization energy loss and time-of-flight information, the ring-imaging Cherenkov technique and the kink-topology identification of weak decays of charged kaons. Transverse momentum spectra are measured from 0.1 up to 3 GeV/cc for pions, from 0.2 up to 6 GeV/cc for kaons and from 0.3 up to 6 GeV/cc for protons. The measured spectra and particle ratios are compared with QCD-inspired models, tuned to reproduce also the earlier measurements performed at the LHC. Furthermore, the integrated particle yields and ratios as well as the average transverse momenta are compared with results at lower collision energies.Comment: 33 pages, 19 captioned figures, 3 tables, authors from page 28, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/156
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