Climate and Dirofilaria infection in Europe

Climatic changes, together with an increase in the movement of cats and dogs across Europe, have caused an increase in the geographical range of several vector borne parasites like Dirofilaria, and in the risk of infection for animals and humans. The present paper reviews the effects of climate and other global drivers on Dirofilaria immitis and Dirofilaria repens infections in Europe and the possible implications on the transmission and control of these mosquito-borne nematodes. In the last several years, growing degree day (GDD)-based forecast models, which use wide or local scale temperature data, have been developed to predict the occurrence and seasonality of Dirofilaria in different parts of the world. All these models are based on the fact that: there is a threshold of 14 °C below which Dirofilaria development will not proceed; and there is a requirement of 130 GDD for larvae to reach infectivity and a maximum life expectancy of 30 days for a vector mosquito. The output of these models predicts that the summer temperatures (with peaks in July) are sufficient to facilitate extrinsic incubation of Dirofilaria even at high latitudes. The global warming projected by the Intergovernmental Panel on Climate Change suggests that warm summers suitable for Dirofilaria transmission in Europe will be the rule in the future decades and if the actual trend of temperature increase continues, filarial infection should spread into previously infection-free areas. These factors not only favour incubation of Dirofilaria, but also impact on mosquito species. Recent findings have also demonstrated that Aedes albopictus is now considered to be an important, competent vector of Dirofilaria infections. This mosquito species could spread from southern to northern European countries in the near future, changing the epidemiological patterns of dirofilariosis both in humans and animals.     

猪传染性胃肠炎临床诊断及防治

猪传染性胃肠炎是由猪传染性胃肠炎病毒引起的急性高度接触性肠道传染病,临床上以腹泻、呕吐和脱水为特征,各种年龄的猪都可发病,对哺乳仔猪的危害最严重.然而以腹泻为主症的还有猪痢疾、仔猪黄痢、仔猪白痢、仔猪红痢(梭菌性肠炎)、流行性腹泻、轮状病毒感染、仔猪副伤寒等7种疫病,为了更有效地防控猪传染性胃肠炎,做到早诊断、早治疗.论文阐述了猪传染性胃肠炎与猪其他7种腹泻疫病的临床症状的区别及猪传染性胃肠炎的防治要点.     

Interactions of prion proteins with soil

Prions, are proteinaceous particles recognized as the agents of a class of neurodegenerative disorders, called transmissible spongiform encephalopathies (TSE), or prion diseases. Epidemiological data suggest that TSE-contaminated environments may serve as source of infectivity, but there is no information about adsorption of prions onto soil. We carried out experiments by mixing, healthy, or scrapie-infected hamster brains homogenates with three types of soil suspended in different buffers: (i) two saline buffers, i.e., phosphate buffer solution (PBS) and CaCl₂ solution; (ii) a mix of nondenaturing detergents, i.e., Triton X-100 and sodium deoxycholate (DOC) solution; (iii) a non-ionic detergent, i.e., lauryl maltoside; (iv) two anionic detergents, i.e., Sarkosyl or sodium dodecyl sulphate (SDS); and (v) a chaotropic agent, i.e., urea. The unbound prion proteins were detected in the supernatants (after centrifugation of soil suspension) by Western blotting. Results clearly demonstrate that both the no infectious (PrP^C) and infectious (PrP^Sc) forms are adsorbed by all soils. Only 1% sodium dodecylsulphate (SDS) partially impeded the association of PrP^C, but not that of PrP^Sc with the sandy loam soil. Agents with different interacting properties towards hydrophilic and/or hydrophobic domains failed to extract PrP^Sc from sediments of soil-brain homogenate mixtures. The strong interaction of PrP^Sc with soil favors the accumulation of prions in soils, especially if amended with prion-containing organic fertilizers and/or whenever TSE-affected animal carcasses, placenta, and excreta in general are buried or laid at the soil surface.     

Replant diseases: Bacterial community structure and diversity in peach rhizosphere as determined by metabolic and genetic fingerprinting

Peach tree replant disease, though reported on in the literature for more than two centuries, has yet to have its causes clearly defined. Decline in peach productivity has been attributed to toxic agents, insects, nutritional disturbances, spray residues, fungi and nematodes. Bacteria has also been indicated as a contributing factor.Peach replant disease was reproduced by using two successive cultures on the same soil. Bacterial communities were isolated and characterized from healthy and diseased peach trees. The potential role of cyanide production by rhizobacteria in the replant problem of peaches was studied. Culture-dependent (evaluation of the number of culturable bacteria, metabolic activities, Biolog^® GN2) and independent (ribosomal intergenic spacer analysis, RISA) methods were used, in order to compare bacterial community structure and diversity in healthy and sick soils and to evaluate the possible role of cyanide.Bacterial densities were significantly increased in sick soils. Metabolic activities (Biolog^® GN2) and genetic structure, observed through RISA, were also significantly modified in sick soils. Changes in the composition of individual microbial groups in the rhizosphere of peach trees excavated from healthy or sick soil indicated the involvement of rhizobacteria in the etiology of the replant sickness of peach soil. More than 60% of the strains isolated from healthy soils corresponded to Pseudomonas sp. and 58% of the isolates from sick soils were Bacillus sp. This study determined that Bacillus were able to produce in vitro HCN. It also appeared that in sick soil, there was a shift in the structure of bacterial communities with an increase noted in phytotoxic microorganisms capable of producing HCN compounds.     

酵母菌对果蔬采后病害防治的研究进展

该文对酵母菌对果蔬采后病害防治的研究现状进行了综述，其中包括防治效果、防治机理、防治的优势及最新研究成果。许多酵母菌对果蔬采后病害具有明显的抑制作用，酵母菌抑制霉菌的机理主要在于营养与空间的竞争、对病原菌的直接寄生作用及诱导寄主产生抗病性。酵母菌与其它生防微生物相比，具有拮抗效果好、不产生毒素、可以和化学杀菌剂共同使用等优点。使用生物工程技术改造拮抗酵母菌从而提高其生防效果，是酵母菌对果蔬采后生物防治的最新研究领域。该文还指出了酵母菌对果蔬采后生物防治存在的问题，并对未来的研究提出了新的思路。     

基于深度学习的作物病虫害可视化知识图谱构建

针对作物病虫害领域存在实体关系交叉关联、多源异构数据聚合能力差、知识共享困难等问题，利用知识图谱以结构化的形式描述实体间复杂关系的优势，该研究提出了一种基于深度学习的作物病虫害知识图谱构建方法。该方法在领域本体的基础上，以一种与领域语料相适应的新标注模式实现实体和关系的联合抽取。将实体和关系抽取任务转化为序列标注问题，对实体和关系进行同步标注，有效提高标注效率；为了解决重叠关系抽取问题，直接对三元组建模而不是分别对实体和关系建模，通过标签匹配和映射即可获得三元组数据。利用来自转换器的双向编码器表征量（Bidirectional Encoder Representations from Transformers，BERT）-双向长短期记忆网络（Bi-directional Long-Short Term Memory，BiLSTM）+条件随机场（Conditional Random Field，CRF）端到端模型进行试验，结果表明效果优于基于普通标注方式的流水线方法和联合学习方法中的卷积神经网络（Convolutional Neural Networks，CNN）+BiLSTM+CRF、BiLSTM+CRF等经典模型，F1得分为91.34%。最后，将抽取到的知识存储到Neo4j图数据库中，直观地反映知识图谱的内部结构，实现知识可视化和知识推理。该研究构建的知识图谱可为作物病虫害智能问答系统、推荐系统、智能搜索等下游应用提供高质量的知识库基础。     

Validation of a multiplex PCR assay to detect Babesia spp. and Anaplasma marginale in cattle in Uruguay in the absence of a gold standard test

Detection of bovine Babesia spp. and Anaplasma marginale is based on the reading of Giemsa-stained blood or organ smears, which can have low sensitivity. Our aim was to improve the detection of bovine Babesia spp. and A. marginale by validating a multiplex PCR (mPCR). We used 466 samples of blood and/or organs of animals with signs and presumptive autopsy findings of babesiosis or anaplasmosis. The primers in our mPCR amplified the rap-1a gene region of Babesia bovis and B. bigemina, and the msp-5 region of A. marginale. We used a Bayesian model with a non-informative priori distribution for the prevalence estimate and informative priori distribution for estimation of sensitivity and specificity. The sensitivity and specificity for smear detection of Babesia spp. were 68.6% and 99.1%, and for A. marginale 85.6% and 98.8%, respectively. Sensitivity and specificity for mPCR detection for Babesia spp. were 94.2% and 97.1%, and for A. marginale 95.2% and 92.7%, respectively. Our mPCR had good accuracy in detecting Babesia spp. and A. marginale, and would be a reliable test for veterinarians to choose the correct treatment for each agent.     

奶牛常见繁殖疾病诊断与治疗

中国乳制品消费水平位于全球前三,奶牛养殖业在国内具有很大的发展潜力。随着奶牛养殖业的发展和扩大,繁殖疾病成为影响奶牛场经济效益的因素之一。繁殖疾病的发生和很多因素有关,包括营养、卫生等方面,体内激素不平衡也会诱发繁殖疾病的发生。本文对引起奶牛繁殖疾病的主要发病原因、临床症状、病理变化、临床诊断及治疗方法进行归纳总结,以期为繁殖疾病的诊断治疗提供理论基础。     

畜牧养殖中动物疾病病因及防控

畜牧养殖是山东省无棣县车王镇的重点产业,近年发展速度较快,显著促进了地区居民的增收致富。在畜牧养殖过程中,动物疾病防控是关键管理环节。为提升动物疾病防控成效,需深入分析动物疾病的出现原因,采取针对性的解决对策,最大程度控制动物疾病的发生与影响。     

烟叶不同生育期病虫害防治要点分析

充分了解和掌握病虫害发生规律及传染途径,做到防重于治,科学、合理、安全使用农药,才能在病虫害防治方面取得明显效果。