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31.
动物应用抗菌药的风险及防制对策   总被引:5,自引:0,他引:5  
食品动物因大量应用抗菌药物产生耐药菌株,对动物和人类健康及生态环境造成危害,为此欧盟对多种促生长抗菌药颁布了禁令,导致了动物治疗用抗菌药的急剧增加及畜牧业经济效益的降低。本文就此展开讨论,强调必须开发新型抗菌药物,合理应用抗菌药,加强抗菌药药效学及药动学研究,健全食源性病原菌耐药性监测系统等。  相似文献   
32.
Because of severe resource and logistical constraints in large areas of Africa, disease surveillance systems need to maximize the use of information provided by livestock keepers and make correct interpretations of indigenous livestock knowledge. This paper describes the use of participatory epidemiology (PE) to compare the names, clinical signs and epidemiological features of cattle diseases as perceived by pastoralists and veterinarians. Using results from two previous studies with pastoralists in southern Sudan and Kenya, provisional translations of local disease names into modern veterinary terminology were used to develop a matrix scoring method for use with veterinarians. Matrix scoring data from pastoralists and veterinarians were then compared using simple visual comparison of summarized matrices, hierarchical cluster analysis and multidimensional scaling. The results showed good agreement between pastoralists' and veterinarians' disease names and diagnostic criteria. The matrix scoring method was easy to use and appropriate for use in under-resourced areas with minimal professional support or laboratory services. Matrix scoring could be used to assist livestock disease surveillance workers to design surveillance systems that make better use of pastoralist's indigenous knowledge and correctly interpret local disease names. The method should be combined with conventional veterinary investigation methods where feasible.  相似文献   
33.
In January 1997, Tanzania requested international assistance against rinderpest on the grounds that the virus had probably entered the country from southern Kenya. Over the next few months, a variety of attempts were made to determine the extent of the incursion by searching for serological and clinical evidence of the whereabouts of the virus. At the clinical level, these attempts were hampered by the low virulence of the strain, and at the serological level by the lack of a baseline against which contemporary interpretations could be made. Once it became apparent that neither surveillance tool was likely to produce a rapid result, an infected area was declared on common-sense grounds and emergency vaccination was initiated. The vaccination programme had two objectives, firstly to prevent any further entry across the international border, and secondly to contain and if possible eliminate rinderpest from those districts into which it had already entered. On the few occasions that clinical rinderpest was subsequently found, it was always within this provisional infected area. Emergency vaccination campaigns within the infected area ran from January to the end of March 1997 but were halted by the onset of the long rains. At this time, seromonitoring in two districts showed that viral persistence was still theoretically possible and therefore a second round of emergency vaccination was immediately organized. Further seromonitoring then indicated a large number of villages with population antibody prevalences of over 85%. These populations were considered to have been `immunosterilized'. Although no clinical disease had been observed in them, it was decided to undertake additional vaccination in a group of districts to the south of the infected area. Serosurveillance indicated that rinderpest could have been present in a number of these districts prior to vaccination. Serosurveillance in 1998 suggested that numerous vaccinated animals had probably moved into districts outside the infected and additional vaccination areas, but did not rule out the continued presence of field infection.  相似文献   
34.
Tsetse have been cleared from large areas of Zimbabwe during the past 65 years. In most areas, they are prevented from re-invading cleared areas by barriers of odour-baited, insecticide-treated targets. A trypanosomosis survey was conducted to determine the effectiveness of such barriers against re-invasion and to confirm the absence of tsetse in areas where they had previously been eradicated. Parasitological diagnostic methods and an anti-trypanosomal antibody detection enzyme-linked immunosorbent assay (antibody ELISA) were used. The prevalence of trypanosomal infections in the tsetse-cleared areas was generally low. However, the prevalence of anti-trypanosomal antibodies was unexpectedly high in some areas. This high proportion of cattle with antibodies could, in most cases, be explained by recent or historic information on the distribution and density of tsetse. The results from the survey demonstrated the value of anti-trypanosomal antibody detection as an additional sensitive tool for monitoring the effectiveness of tsetse control operations.  相似文献   
35.
Neophysopella tropicalis, one of the causal agents of Asian grapevine leaf rust (AGLR), can cause severe epidemics in Brazil that lead to yield losses in commercial vineyards. An early detection of the pathogen by air sampling of urediniospores on spore traps or in symptomless leaves would be valuable to multiple studies, such as epidemics modelling, risk forecasting, monitoring of pathogen introductions in rust-free areas, and predicting the beginning of epidemics. This study developed a quantitative PCR (qPCR) protocol to quantify N. tropicalis urediniospores attached to adhesive tapes and in grapevine leaves before symptom appearance. A specific primer pair was designed based on the internal transcribed spacer (ITS) sequence region of the AGLR pathogen. Standard amplification curves using genomic DNA from urediniospores of N. tropicalis and from urediniospores attached to adhesive tapes were established. Grapevine leaves inoculated with N. tropicalis were collected at 2, 5, and 7 days postinoculation (dpi). One primer pair (580F/720R) amplified a 140 bp product in all AGLR isolates but did not amplify products of other rust genera, such as Phakopsora, Puccinia, Hemileia, Tranzschelia, Cerotelium, and Coleosporium. As little as 0.1 pg DNA and 10 urediniospores of N. tropicalis attached to adhesive tapes could be detected. qPCR enabled the detection of the pathogen as early as 2 dpi, before symptom appearance. This method can be used to monitor N. tropicalis inoculum in grapevine-growing areas and to quantify symptomless infections of the AGLR pathogen.  相似文献   
36.
应用RT-PCR技术开展云南省种公猪精液中乙型脑炎病毒(JEV)感染监测,进而对阳性样品病毒基因扩增产物进行克隆、测序、比对及系统发育分析。从云南省16个地州797份猪精液中检出JEV阳性样品7份,阳性率0.88%。阳性精液样品中的JEV与基因Ⅰ型毒株PrM基因核苷酸序列同源性为97.5%~98.8%,与其他基因型毒株的同源性介于76.9%~89.8%之间,与疫苗毒株(基因Ⅲ型毒株,S19980008)的同源性为89.1%~89.8%。云南省种公猪精液中JEV属于基因Ⅰ型毒株,与人、猪、蚊虫基因Ⅰ型分离毒株遗传关系密切。  相似文献   
37.
Between 1950 and 1989, marine fisheries catch in the open‐ocean and deep‐sea beyond 200 nautical miles from shore increased by a factor of more than 10. While high seas catches have since plateaued, fishing effort continues to increase linearly. The combination of increasing effort and illegal, unreported and unregulated (IUU) fishing has led to overfishing of target stocks and declines in biodiversity. To improve management, there have been numerous calls to increase monitoring, control and surveillance (MCS). However, MCS has been unevenly implemented, undermining efforts to sustainably use high seas and straddling stocks and protect associated species and ecosystems. The United Nations General Assembly is currently negotiating a new international treaty for the conservation and sustainable use of biodiversity beyond national jurisdiction (BBNJ). The new treaty offers an excellent opportunity to address discrepancies in how MCS is applied across regional fisheries management organizations (RFMOs). This paper identifies ways that automatic identification system (AIS) data can inform MCS on the high seas and thereby enhance conservation and management of biodiversity beyond national jurisdictions. AIS data can be used to (i) identify gaps in governance to underpin the importance of a holistic scope for the new agreement; (ii) monitor area‐based management tools; and (iii) increase the capacity of countries and RFMOs to manage via the technology transfer. Any new BBNJ treaty should emphasize MCS and the role of electronic monitoring including the use of AIS data, as well as government–industry–civil society partnerships to ensure critically important technology transfer and capacity building.  相似文献   
38.
39.
喻成林  黄强 《安徽农业科学》2013,(36):14104-14106
[目的]建设用地批后监管工作一直是国土资源管理的薄弱环节,解决缺乏动态监管的有效途径和技术,引起的信息获取速度慢、共享程度低等问题.[方法]对目前GIS技术和视频监控技术进行了研究,将GIS技术和视频监控技术相结合,应用于建设用地批后监管信息系统中.[结果]研究了基于GIS的建设用地批后视频监控系统的功能特点、整体架构的设计以及实现该系统的思路.[结论]创新了国土资源执法的监管方式,改进了传统监管方式的不足,实现了由被动执法向主动防范的转变.  相似文献   
40.
We report a fall 2010 cluster of pandemic influenza A/H1N1 (pH1N1) infections in pet ferrets in Lehigh Valley region of Pennsylvania. The ferrets were associated with one pet shop. The influenza cluster occurred during a period when the existing human surveillance systems had identified little to no pH1N1 in humans in the Lehigh Valley, and there were no routine influenza surveillance systems for exotic pets. The index case was a 2.5‐month‐old neutered male ferret that was presented to a veterinary clinic with severe influenza‐like illness (ILI). In response to laboratory notification of a positive influenza test result, and upon request from the Pennsylvania Department of Health (PADOH), the Pennsylvania Department of Agriculture (PDA) conducted an investigation to identify other ill ferrets and to identify the source and extent of infection. PDA notified the PADOH of the pH1N1 infection in the ferrets, leading to enhanced human surveillance and the detection of pH1N1 human infections in the surrounding community. Five additional ferrets with ILI linked to the pet shop were identified. This simultaneous outbreak of ferret and human pH1N1 demonstrates the important link between animal health and public health and highlights the potential use of veterinary clinics for sentinel surveillance of diseases shared between animals and humans.  相似文献   
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