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1.
应用已建立的鸡肿瘤病快速鉴别诊断技术对源自安徽省5个不同地区的46个鸡群的肿瘤病、抑制病疑似病、死鸡305羽进行检测。结果表明,马立克氏病的阳性率为39.34%(120/305),禽网状内皮组织增生征阳性率为8.52%(26/305),禽白血病阳性率为2.624%(8/305);另对17群未进行MD免疫的肉鸡进行随机抽样检测,其中5个鸡群检测出马立克氏病病毒强毒,阳性率为29.41%(5/17),阳性群的平均检出率为24 %。  相似文献   
2.
姚州  谭焓  田芳  周勇  章程 《中国饲料》2021,1(7):7-12
智慧羊场具有科学化、标准化管理的优点,是羊场转型发展的趋势。计算机视觉技术是人工智能的核心,可以实现非接触性、自动化、实时监测羊的个体信息。本文总结并分析了计算机视觉在羊场的个体识别方法、行为识别方法、体尺与体重估测、疾病监测的研究现状,并指出计算机视觉在智慧羊场的进一步发展趋势。 [关键词] 计算机视觉|智慧羊场|个体识别|行为识别|体尺与体重估测|疾病监测  相似文献   
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网络舆情错综复杂,现有的手工方式已无法满足互联网舆情实时监测与分析的要求,构建网络舆情监测信息系统是及时了解民意、掌握热点、发现与化解社会问题的必由之路;网络舆情监测系统就是运用信息自动发现与搜集、智能识别与处理等多种技术,能够满足指定主题自动发现与跟踪、舆情统计分析与热点趋势预测、正面言论回复与积极舆论引导等功能要求,是网络信息预警的重要组成部分。  相似文献   
5.
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   
6.
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   
7.
本文介绍了丹麦有机猪的生产情况(有机猪的品种、畜舍环境和条件、畜舍卫生和饲养饲料状况)、沙门氏菌控制计划的情况(饲料、种猪群、断奶仔猪群、育肥猪群和屠宰场的监控)和效果。同时,简析了我国发展有机畜牧业的必要性,最后提出实行危害分析和关键控制点(HACCP)预防管理体系和有机养殖是我国养猪业的发展方向。  相似文献   
8.
李毅  肖中琪  金隆 《林业调查规划》2015,40(1):111-114,119
基于移动通信、地理信息和视频监控等技术建立天然林资源保护工程智能化监控平台,实现天然林资源的全面监控和管理,加强巡护人员和巡护事件的监控力度。文中介绍了视频监控技术、移动GIS技术和智能移动通信技术等研究中的关键技术。阐述平台总体框架设计以及视频监控管理子系统、天保工程森林智能移动巡护子系统和天然林资源保护巡护管理子系统的主要功能实现。  相似文献   
9.
贵州省退耕还林工程生态效益监测与评价初探   总被引:4,自引:0,他引:4  
通过对贵州省退耕还林10个生态效益监测网络县设置的100个坡面固定样地,以及5个典型县16个坡面径流场各生态指标2年观测数据的分析,得出退耕还林后监测区各生态指标的改善情况如下:退耕还林后2年内土壤侵蚀模数和流失量减少78%,监测区植被覆盖率由12.4%增加到38.7%,平均综合生态效益指数已由0.18上升到0.53。  相似文献   
10.
In 2010, a West Nile virus (WNV) epidemic was reported in Central Macedonia, Northern Greece, with 197 neuroinvasive disease (WNND) cases in humans. The following 3 years, WNV spreads to new areas of Greece and human cases reoccurred during the transmission periods. After the initial outbreak, a WNV surveillance system using juvenile backyard chickens was established in Central Macedonia (after the 2011 outbreak) and Eastern Macedonia‐Thrace (after the 2012 outbreak). Sera were screened for the presence of antibodies against WNV using cELISA and serum neutralization test, to monitor the spread of WNV and to assess the correlation between the WNV point seroprevalence in chickens and the incidence rates of human WNND cases in the aforementioned areas. WNV seroprevalence in chickens was 10.4% (95% CI: 7–15) in Central Macedonia (2011) and 18.1% (95% CI: 14–23) in Eastern Macedonia‐Thrace (2012). Seroprevalence in chickens and incidence rates of human WNND cases in Eastern Macedonia‐Thrace were strongly positively correlated (ρ = 0.98, P = 0.005) at the regional unit level, with the incidence of WNND in humans increasing with increasing WNV point seroprevalence in chickens. In Central Macedonia, the correlation was weaker (ρ = 0.68, P = 0.20), apparently due to small number of reported human WNND cases. Another study was also conducted using juvenile backyard chickens in Central Macedonia, aiming to detect early WNV enzootic circulation, before the onset of human cases during 2011 and 2013. The first seroconverted chickens were detected about 1.5 months before the laboratory diagnosis of any human WNND cases in Central Macedonia, for both years. WNV surveillance, using juvenile backyard chickens, was reliable for the identification of areas with WNV enzootic and silent transmission, and for early warning. Timely diffusion of information to public health authorities facilitated the successful implementation of preparedness plans to protect public health.  相似文献   
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