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51.
The aim of the present study was to investigate the contamination sources and the transmission of Salmonella within a pig finishing herd in Italy. Nine sets of samples were collected during the fattening period from cleaned and disinfected pens, animals at different ages (4 days after arrival, 90, 150, 170 and 240 days of age) and at slaughter. Salmonella was isolated from cleaned pens, individual faecal samples, the truck used to transport the pigs to the abattoir and after slaughter (cecal contents, mesenteric lymph nodes and carcasses). Several serovars were isolated: Salmonella typhimurium and Salmonella derby on farm; Salmonella bovismorbificans, Salmonella bredeney, Salmonella blockley, Salmonella hadar and Salmonella corvallis from the truck; S. derby, S. hadar, S. bredeney, S. bovismorbificans and Salmonella infantis at slaughter. Antibiotic resistance of the strains was tested and PFGE was carried out to investigate the on-farm epidemiology of Salmonella. The results showed that the environmental contamination may have represented a major source of infection for the pigs both on farm and during transport to the abattoir.  相似文献   
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Multilobular tumour of bone is a rare neoplasm of the skull in middle-aged, medium-to-large breed dogs even if a few cases have also been described in cats and one horse. The aim of the present paper is to show both the computed-tomography features and the pathological findings of the above neoplasm affecting the thoracic wall of a cat. To the best of the authors' knowledge, such anomalous tumour localisation has never been reported and imaged in feline medicine.  相似文献   
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Many conservation and restoration efforts in developed countries are increasingly based on the premise of recognising and stimulating more ‘multi-functionality’ in agricultural landscapes. Public policy making is often a pragmatic process that involves efforts to negotiate trade-offs between the potentially conflicting demands of various stakeholders. Conservationists’ efforts to influence policy making, can therefore benefit from any tool that will help them to identify other socio-economic functions or values that coincide with good ecological conservation options. Various types of socio-economic objectives have in recent years been mapped across landscapes and so there are now important opportunities to explore the spatial heterogeneity of these diverse functions across the wider landscape in search of potential spatial synergies, i.e. ‘multiple win locations’ or multifunctional ‘hotspots’. This paper explores the potential occurrence of such synergies within the agricultural landscape of northeast Scotland and evaluates an existing woodland planting policy using and combining three different policy objectives. Our results show that there are indeed broad areas of the studied landscape where multiple objectives (biodiversity, visual amenity and on-site recreation potential) could be achieved simultaneously (hotspots), and that the case study which we evaluate (the Farm Woodland Premium Scheme) could be much better spatially targeted with regards to each individual objective as well as with regards to these hotspots of multifunctionality.
Dan van der HorstEmail:
  相似文献   
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Vitellogenin (Vtg) has proven to be a sensitive and simple biomarker in determining sex, sexual maturity, and xenoestrogenic effects in fish. Thus, our investigation has been focused on identification, partial characterization, and quantification of grey mullet (Mugil cephalus) Vtg through the use of a variety of biochemical and immunological analytical techniques. Mullet is considered both a promising aquaculture candidate and an important species for improving sediment quality in polyculture systems. In the first part of this work, grey mullet Vtg was purified from plasma of 17β-estradiol (E2)-induced male fish by a one-step chromatographic protocol, and partially characterized. Specific polyclonal antibodies were then raised against the mullet Vtg, and both an indirect ELISA and an optical immunosensor were set up and validated to quantify plasma Vtg. The indirect ELISA and the optical immunosensor assay developed showed linear measuring in the range 56.8–1047.1 ng mL−1 and 70–739 ng mL−1 Vtg concentrations in standard solutions, respectively. The results obtained suggest that the indirect ELISA allows Vtg detection over a wide dynamic range, thus resulting more suitable for rapid and sensitive sample screening. Therefore, we suggest that the direct immunosensor is a promising tool which needs more investigation to improve the sensitivity.  相似文献   
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Bacterial epiphytes isolated from marine eukaryotes were screened for the production of quorum sensing inhibitory compounds (QSIs). Marine isolate KS8, identified as a Pseudoalteromonas sp., was found to display strong quorum sensing inhibitory (QSI) activity against acyl homoserine lactone (AHL)-based reporter strains Chromobacterium violaceum ATCC 12472 and CV026. KS8 supernatant significantly reduced biofilm biomass during biofilm formation (−63%) and in pre-established, mature P. aeruginosa PAO1 biofilms (−33%). KS8 supernatant also caused a 0.97-log reduction (−89%) and a 2-log reduction (−99%) in PAO1 biofilm viable counts in the biofilm formation assay and the biofilm eradication assay respectively. The crude organic extract of KS8 had a minimum inhibitory concentration (MIC) of 2 mg/mL against PAO1 but no minimum bactericidal concentration (MBC) was observed over the concentration range tested (MBC > 16 mg/mL). Sub-MIC concentrations (1 mg/mL) of KS8 crude organic extract significantly reduced the quorum sensing (QS)-dependent production of both pyoverdin and pyocyanin in P. aeruginosa PAO1 without affecting growth. A combinatorial approach using tobramycin and the crude organic extract at 1 mg/mL against planktonic P. aeruginosa PAO1 was found to increase the efficacy of tobramycin ten-fold, decreasing the MIC from 0.75 to 0.075 µg/mL. These data support the validity of approaches combining conventional antibiotic therapy with non-antibiotic compounds to improve the efficacy of current treatments.  相似文献   
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Journal of Plant Diseases and Protection - The disease reducing activity of acibenzolar-S-methyl (ASM), chitosan and β-aminobutyric acid (BABA) against postharvest green mold (GM) of citrus...  相似文献   
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采用固体交叉极化魔角自旋13C核磁共振(CPMAS13C-NMR)波谱技术对长期不同施肥处理下红壤性水稻土和太湖地区黄泥土本体土壤以及水稳性团聚体中颗粒有机质(POM)的化学结构特征进行了研究。结果表明,不同施肥处理下本体土壤和不同粒径水稳性团聚体中POM的结构组成相似,主要由烷氧C、烷基C和芳香C组成,其中以烷氧C含量最高。施肥改变了本体土壤POM中各类C原子的相对百分含量,有机肥以及化肥配施有机肥条件下烷氧C含量明显降低,芳香C和酚基C含量有不同程度的增加,表明POM的稳定性增强;单施化肥下烷氧C含量最高,而烷基C、芳香C和芳香度均最低,POM的稳定性减弱,不利于POM的积累。施肥改变了黄泥土不同粒径水稳性团聚体中POM各类C原子的相对百分含量,从而使得不同粒径中POM对其团聚体的稳定性作用发生变化;而红壤性水稻土不同粒径水稳性团聚体POM各类C原子的相对百分含量并未明显受到施肥措施的影响。  相似文献   
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