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71.
This article was motivated by the US Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) announcement that on 17 December 2021 it rescinded Federal Orders of 2 May 2007 that regulated (what was believed to be) a new outbreak of the light brown apple moth (LBAM, Epiphyas postvittana (Walker)) in the mainland United States. Our article follows from, and builds on, a 2013 article published by Carey and Harder that outlined major concerns about the LBAM eradication program including the need, cost, safety, practicality, and feasibility of the program and the public opposition to it. The program began with an emergency order based on USDA claims of billions of dollars in potential crop losses and the need to circumvent safety review processes to urgently prevent the pest's establishment. The program ended with the realization by government decision-makers, 14 years after initiating the program, that LBAM posed no quarantine-level threat in the first place and with no evidence of any economic damage done by the insect. This article summarizes the mistakes made in devising and carrying out what has ultimately proven to be one of the most oversold, overhyped, misguided, ill-advised, unnecessary, and costly programs in the recent history of insect eradication programs in California. Termination of the LBAM program by USDA-APHIS presents an opportunity to review the program to identify lessons learned and provide recommendations to help avoid similar mistakes in future invasive species response programs. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
72.
我国牛羊源人畜共患病的防控现状   总被引:1,自引:0,他引:1  
我国牛羊业迅速发展同时增加了包括布鲁氏菌病、结核病、血吸虫病和包虫病等牛羊源人兽共患病的流行风险。本文具体介绍了我国人兽共患病的流行现状,从健全法规、完善补偿制度、加强检验和流动控制、加快相关技术的研发进程等政策层面上对影响防控效果的主要问题进行了分析,以期为提高我国牛羊源人兽共患病防控水平提供帮助。  相似文献   
73.
苏皖地区规模化鸡场禽白血病净化的初步研究   总被引:2,自引:0,他引:2  
基于苏皖地区禽白血病(AL)流行病学调查结果,本研究参考国际AL净化方案,针对该病在苏皖地区的流行特点,选择代号为DYAH91和DYJS31的两个规模化地方品系鸡群开展了禽白血病净化初步研究。经过一个世代的净化更替,DYAH91鸡群p27抗原阳性率由14.4%下降到8.1%,p27抗体阳性率由3.4%下降到1.0%,A/B亚群抗体阳性率由5.7%下降到2.2%,病毒分离阳性率由3.1%下降到0.45%;DYJS31鸡群,p27抗原阳性率由40.7%下降到2.8%,p27抗体阳性率由18.7%下降到3.3%,A/B亚群抗体阳性率由10.2%下降到1.4%,J亚群抗体由1.7%下降到1.4%,病毒分离阳性率由4.1%下降为0。以上结果表明通过净化程序的实施,鸡群ALV阳性率显著下降,净化方案效果确实。  相似文献   
74.
较系统地介绍了采用物理与化学相结合的方法,快速破除木包装中松材线虫幼虫休眠期,加速休眠幼虫转变为成虫,促进休眠幼虫的分离数量,缩短检疫时间,提高松材线虫的检出率。  相似文献   
75.
76.
研究在2012~2016年间对原种场A、B、C和D4个地方鸡种保种核心群开展了禽白血病净化,通过新建净化鸡舍,采用严格净化技术方案,在强化饲养管理的基础上,经过2~3个世代净化,各品种鸡群取得了显著净化效果。A鸡种经过3个世代净化,25~27周龄蛋清p27抗原阳性率由26.4%降至0.3%,36~40周龄血浆病毒分离阳性率由36.4%降至0.4%,种公鸡病毒分离阳性率连续2个世代均为零;B鸡种经过3个世代净化,6周龄血浆病毒分离阳性率由33.2%降至1.2%,36~40周龄蛋清p27抗原和血浆病毒分离阳性率均降至零;C鸡种经过2个世代净化,留种前血浆病毒分离阳性率由61.8%降至0.9%;D鸡种经过2个世代净化,留种前蛋清p27抗原阳性率由20.7%降至1.9%,血浆病毒分离阳性率降至0.2%。禽白血病净化对种鸡生产性能的影响,以A鸡种为例,经过3个世代净化,育雏期、育成期和产蛋期死亡率均逐级下降,净化第一世代效果最为显著;产蛋性能亦明显提高,43周龄总产蛋数平均增加了13个/只,66周龄总产蛋数平均增加了23个/只。研究为众多地方品种鸡群及原种场禽白血病净化起到了良好示范作用。  相似文献   
77.
Since 1998, there has been a steady decline in herd restrictions and de-populations in Ireland due to bovine brucellosis. There is concern that the interpretation of laboratory results may become increasingly problematic, as brucellosis prevalence falls in Ireland. Therefore, the purpose of the current study was to evaluate the infection status of Irish herds and animals with inconclusive serological evidence of bovine brucellosis. During 12 months from September 1, 2004, laboratory and observational epidemiological data were collected from all Irish herds where animal testing identified at least one animal with a complement fixation test (CFT) reading greater than zero and/or a positive result to the indirect enzyme-linked immunosorbent assay (iELISA). Due to the observational nature of the study, we have robust estimates of the relative, but not the absolute, performance of the CFT, iELISA and brucellin skin test (BST). Herds were divided into three categories (Group A, B or C) on the basis of test results at initial assessment. A total of 639 herds were enrolled into the study, and observed for at least two years following enrolment. A rising CFT titre, with a CFT reading of 111 International CFT Units (IU) or greater at the subsequent blood test, was generally associated with herds where other evidence of infection was also available. Knowledge of the CFT reading at the initial and a subsequent blood test proved useful in distinguishing false-positive and true-positive brucellosis results. There was poor correlation between the CFT and iELISA results, and between the CFT and BST results. As a result of this study, national policy has been modified to include re-sampling of all animals with CFT readings of 20 IU or greater. This project has also led to a reduction in the number of herds restricted, as well as restriction duration. It has also contributed to a reduction in the number of herds listed for contiguous tests, and therefore the potential for contiguity testing of false positive results.  相似文献   
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79.
OBJECTIVE: To determine sheep farmers' attitudes to and beliefs about ovine footrot, and to improve their knowledge about the diagnosis, control and eradication of this disease. METHOD: Eighteen workshops, involving 291 farmers, were conducted across Victoria in the spring of 1996. The workshops were designed as small-group discussions with a maximum attendance of 20 farmers to encourage active participation. All participants completed questionnaires before each workshop and 12 to 40 weeks after the last workshop. RESULTS: Before the workshops the farmers had a poor understanding of the principles of diagnosis, control and eradication of footrot. For example, only 50% knew the footrot organism survived in soil for less than 7 days, over two-thirds did not know the reason for paring sheep's feet during an eradication program, and only 31% realised cattle were a potential source of footrot infection for sheep. After the workshops, understanding about footrot was significantly improved; 87% said Dichelobacter nodosus survived in soil less than 7 days, 71% knew the reason for paring sheep's feet and 64% realised that cattle were a potential source of footrot infection. As well as improved knowledge, change of attitude among farmers is fundamentally important if virulent footrot is to be successfully controlled and eradicated. The workshops successfully initiated this process; 40% of farmers thought the workshops changed their attitudes to footrot, while 37% said they gained an increased understanding of other people's opinions about the disease. CONCLUSION: Farmers' poor understanding of ovine footrot is a constraint to the programs aimed at controlling this disease. Small group workshops may be an effective way to influence farmers' attitudes and beliefs, and could facilitate the effectiveness of regulatory disease control programs.  相似文献   
80.
In 1983 and 1987/88 two limited outbreaks of zucchini yellow mosaic virus in cucumber and zucchini squash occurred in the Westland glasshouse district in the Netherlands, mainly in glasshouses. The disease could be eradicated and has not recurred so far. In both cases a relatively mild but still highly pathogenic strain of the virus was involved. Diseased plants of zucchini yielded severely distorted or no fruits and it was difficult to obtain seeds from infected plants. Two out of 4196 seedlings grown in isolation from seed from inoculated zucchini plants showed symptoms and contained the virus, indicating that the virus can be transmitted via seed but at very low rate. This explains the erratic incidence and international distribution of the virus.  相似文献   
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