Hennig-Pauka Isabel, Imker Rabea, Mayer Leonie, Brügmann Michael, Werckenthin Christiane, Weber Heike, Menrath Andrea, de Buhr Nicole
Field Station for Epidemiology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany.
Department of Physiological Chemistry, University of Veterinary Medicine Hannover, 30559 Hannover, Germany.
Pathogens. 2019 Nov 20;8(4):249. doi: 10.3390/pathogens8040249.
Swine stocks are endemically infected with the major porcine pathogen () . The factors governing the transition from colonizing residing in the tonsils and the exacerbation of disease have not yet been elucidated. We analyzed the sudden death of fattening pigs kept under extensive husbandry conditions in a zoo. The animals died suddenly of septic shock and showed disseminated intravascular coagulopathy. Genotypic and phenotypic characterizations of the isolated strains, a tonsillar isolate and an invasive type 2 strain, were conducted. Isolated from dead pigs belonged to type 2 strain ST28, whereas one tonsillar isolate harvested from a healthy animal belonged to ST1173. Neither growth, induction of neutrophil extracellular traps, nor survival in blood could explain the sudden deaths. Reconstituted blood assays with serum samples from pigs of different age groups from the zoo stock suggested varying protection of individuals against pathogenic type 2 strains especially in younger pigs. These findings highlight the benefit of further characterization of the causative strains in each case by sequence typing before autologous vaccine candidate selection.
猪群普遍感染主要的猪病原体（）。目前尚未阐明决定从定植于扁桃体的状态转变以及疾病加重的因素。我们分析了动物园中在粗放式饲养条件下饲养的育肥猪突然死亡的情况。这些动物因感染性休克突然死亡，并表现出弥散性血管内凝血。对分离出的菌株进行了基因型和表型特征分析，包括一株扁桃体分离株和一株侵袭性2型菌株。从死猪中分离出的菌株属于2型菌株ST28，而从健康动物采集的一株扁桃体分离株属于ST1173。无论是菌株生长、中性粒细胞胞外陷阱的诱导，还是在血液中的存活，都无法解释这些突然死亡的情况。用来自动物园猪群不同年龄组猪的血清样本进行的重组血液试验表明，个体对致病性2型菌株的保护作用各不相同，尤其是在幼猪中。这些发现凸显了在选择自体候选疫苗之前，通过序列分型对每种情况下的致病菌株进行进一步特征分析的益处。
