Käppeli Nadine, Morach Marina, Zurfluh Katrin, Corti Sabrina, Nüesch-Inderbinen Magdalena, Stephan Roger
Vetsuisse Faculty, Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland.
Front Vet Sci. 2019 Jul 16;6:234. doi: 10.3389/fvets.2019.00234. eCollection 2019.
Bovine mastitis is one of the most common diseases among dairy cows and causes high economic losses in dairy industries worldwide. is one of the most frequently identified pathogens causing the disease. In this study, 153 strains isolated from mastitis milk samples were analyzed for their genetic diversity using multi locus sequence typing (MLST). Moreover, antibiotic susceptibility testing was performed using a microdilution assay and 11 antimicrobial agents including penicillin, which is the first line agent for treatment of bovine mastitis in Switzerland. MLST was successful for 152 (99.3%) of the strains. Overall, 103 different sequence types (STs) were determined, including 91 novel STs. belonging to clonal complex (CC) 5 represented 47 (30.7%) of the mastitis cases. Two (1.3%) of the strains belonged to CC86 and one (0.7%) to CC143. The population structure identified in this work suggests that environmental transmission is the predominant route of infection in herds in Switzerland. Antimicrobial susceptibility testing determined a resistance rate of 11.8% for pirlimycin and elevated MIC90-values for marbofloxacin as well as for erythromycin. This study highlights the importance of genetic characterization of and the need for veterinary breakpoints for surveillance of antimicrobial resistance in .
牛乳腺炎是奶牛中最常见的疾病之一，在全球乳制品行业造成了巨大的经济损失。 是导致该疾病最常被鉴定出的病原体之一。在本研究中，使用多位点序列分型（MLST）对从乳腺炎乳汁样本中分离出的153株菌株进行了遗传多样性分析。此外，使用微量稀释法和包括青霉素（瑞士治疗牛乳腺炎的一线药物）在内的11种抗菌剂进行了药敏试验。152株（99.3%）菌株成功进行了MLST分型。总体而言，确定了103种不同的序列类型（STs），包括91种新的STs。属于克隆复合体（CC）5的菌株占乳腺炎病例的47株（30.7%）。2株（1.3%）菌株属于CC86，1株（0.7%）属于CC143。本研究确定的群体结构表明，环境传播是瑞士牛群中主要的感染途径。药敏试验确定吡利霉素的耐药率为11.8%，马波沙星和红霉素的MIC90值升高。本研究强调了对 进行基因特征分析的重要性以及在 中监测抗菌药物耐药性的兽医断点的必要性。
