中文摘要：瑞士于2004年启动了猪肺炎支原体引起的地方流行性肺炎的净化项目，净化范围包括所有的育肥猪场和部分育种猪场，这一项目的开展使得2003-2013年间支原体的感染病例大幅度下降。然而，近几年地方流行性肺炎的感染数量略有上升。因此，研究开展了肺炎支原体不同品系的分型以阐明支原体感染的源头与路径。研究采用扩展多位点序列分型（MLST）法分析了2014-2016年间22个猪场的序列分析。结果表明，2014/2015年间，大多数猪场流行的肺炎支原体类型主要有两种，每一种都包含6个猪场，分布于5-6个州。通过比较已获得的序列信息，部分序列类型流行时间在10年以上，说明这些类型的序列在瑞士持续时间较长，且之前采取的肺炎支原体净化项目对这些病原品系没有产生作用。感染猪场低效的预防接种体系以及转群时病猪症状不明显，这两个因素导致疾病再次复发。在野生公猪群体内鉴定得到的肺炎支原体品系由于缺乏确凿数据，无法证实野生猪群体是否是这些品系的源头。对野生群体进行监测并对现有猪场可获得的样本进行基因分型或许能够填补现有地方流行性肺炎净化项目的不足。最新的PubMLST序列数据库中提供了肺炎支原体的不同序列类型，能够实现在国际水平上进行肺炎支原体品系的溯源。
 
外文摘要：Enzootic pneumonia (EP) in pigs caused by Mycoplasma (M.) hyopneumoniae has successfully been combatted in Switzerland. A control program was fully implemented in 2004 which is based on total depopulation strategies of affected fattening farms as well as partial depopulation on breeding farms. Thereby, the number of cases has dropped drastically from more than 200 in 2003 to two cases in 2013. Currently monitoring is done based on clinical observation and subsequent diagnostic of coughing pigs. Moreover, in case of more than 10% gross pathological lesions per slaughter batch laboratory confirmation for EP is compulsory. Despite these strict measures it was not possible to eliminate M. hyopneumoniae from Swiss pig production. In fact, during the last few years the number of EP cases has slightly increased. Therefore, genotyping of the involved M. hyopneumoniae strains was conducted in order to elucidate possible sources and routes of infection. All available and typeable samples from totally 22 cases during the period 2014-2016 were investigated by extended multilocus sequence typing (MLST). A total of 16 cases, including eight from 2014, five from 2015 and three from 2016 could thereby be included in the study. MLST revealed that the majority of cases in 2014/2015 were due to two major spread scenarios, i.e. two M. hyopneumoniae sequence types, each scenario involving six individual production farms in five to six different Cantons (states), respectively. Moreover, by comparison of archived sequences some sequence types were observed over ten years demonstrating their persistence over a long time and the possible partial failure of elimination measures in Switzerland. Insufficient sanitation on affected farms and subsequent animal transport of symptomless infected pigs could lead to recurrent cases. Wild boar harbor identical strains found with EP but solid data are missing to assign a role as reservoir to this wild animal. Implementing a monitoring scheme for M. hyopneumoniae in wild boar in combination with genotyping of all available samples from domestic pigs could direct responsible authorities to possible gaps and deficiencies of control measures taken for combating enzootic pneumonia. With the newly installed PubMLST database sequence types for M. hyopneumoniae are now available and allow tracing back strains on the international level.
外文关键词：Epidemiology； Genotyping； Swine disease； Eradication； MLST； p146
作者：Overesch, G; Kuhnert, P
作者单位：伯尔尼大学
期刊名称：PREVENTIVE VETERINARY MEDICINE
期刊影响因子：2.2
出版年份：2017
出版刊次：9
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