Dohmen Wietske, Dorado-García Alejandro, Bonten Marc J M, Wagenaar Jaap A, Mevius Dik, Heederik Dick J J
Department of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, the Netherlands.
Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands.
PLoS One. 2017 Mar 21;12(3):e0174094. doi: 10.1371/journal.pone.0174094. eCollection 2017.
The presence of extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-E. coli) in food animals is a public health concern. This study aimed to determine prevalence of ESBL-E. coli on pig farms and to assess the effect of reducing veterinary antimicrobial use (AMU) and farm management practices on ESBL-E. coli occurrence on pig farms. During 2011-2013, 36 Dutch conventional pig farms participated in a longitudinal study (4 sampling times in 18 months). Rectal swabs were taken from 60 pigs per farm and pooled per 6 pigs within the same age category. Presence of ESBL-E. coli was determined by selective plating and ESBL genes were characterized by microarray, PCR and gene sequencing. An extensive questionnaire on farm characteristics and AMU as Defined Daily Dosages per Animal Year (DDDA/Y) was available for the 6-month periods before each sampling moment. Associations between the presence of ESBL-E. coli-positive pigs and farm management practices were modelled with logistic regression. The number of farms with ESBL-E. coli carrying pigs decreased from 16 to 10 and the prevalence of ESBL-E. coli-positive pooled pig samples halved from 27% to 13%. Overall, the most detected ESBL genes were blaCTX-M-1, blaTEM-52 and blaCTX-M-14. The presence of ESBL-E. coli carrying pigs was not related to total AMU, but it was strongly determined by the presence or absence of cephalosporin use at the farm (OR = 46.4, p = 0.006). Other farm management factors, related with improved biosecurity, were also plausibly related to lower probabilities for ESBL-E. coli-positive farms (e.g. presence of a hygiene lock, pest control delivered by a professional). In conclusion, ESBL-E. coli prevalence decreased in pigs during 2011 and 2013 in the Netherlands. On pig farms, the use of cephalosporins was associated with the presence of ESBL-E. coli carrying pigs.
食用动物中携带超广谱β-内酰胺酶的大肠杆菌（ESBL-E. coli）的存在是一个公共卫生问题。本研究旨在确定猪场中ESBL-E. coli的流行情况，并评估减少兽医抗菌药物使用（AMU）和农场管理措施对猪场中ESBL-E. coli发生情况的影响。在2011年至2013年期间，36个荷兰传统猪场参与了一项纵向研究（18个月内进行4次采样）。每个猪场从60头猪中采集直肠拭子，并按相同年龄类别每6头猪合并为一组。通过选择性平板培养确定ESBL-E. coli的存在，并通过微阵列、PCR和基因测序对ESBL基因进行特征分析。在每个采样时刻前的6个月期间，可获得一份关于农场特征和以每头动物每年限定日剂量（DDDA/Y）表示的AMU的详细问卷。使用逻辑回归对ESBL-E. coli阳性猪的存在与农场管理措施之间的关联进行建模。携带ESBL-E. coli的猪的农场数量从16个减少到10个，ESBL-E. coli阳性合并猪样本的流行率从27%减半至13%。总体而言，检测到最多的ESBL基因是blaCTX-M-1、blaTEM-52和blaCTX-M-14。携带ESBL-E. coli的猪的存在与总AMU无关，但很大程度上取决于农场是否使用头孢菌素（OR = 46.4，p = 0.006）。其他与提高生物安全相关的农场管理因素，也可能与ESBL-E. coli阳性农场的概率较低有关（例如存在卫生锁、由专业人员进行害虫控制）。总之，2011年至2013年期间荷兰猪中ESBL-E. coli的流行率有所下降。在猪场中，头孢菌素的使用与携带ESBL-E. coli的猪的存在有关。
