Gallibacterium anatis is an opportunistic pathogen, previously associated with deaths in poultry, domestic birds, and occasionally humans. We obtained G. anatis isolates from bronchoalveolar lavage samples of 10 calves with bronchopneumonia unresponsive to antimicrobial therapy. Collected isolates were multidrug-resistant to extensively drug-resistant, exhibiting resistance against 5–7 classes of antimicrobial drugs. Whole-genome sequencing revealed 24 different antimicrobial-resistance determinants, including genes not previously described in the Gallibacterium genus or even the Pasteurellaceae family, such as aadA23, bla_CARB-8, tet(Y), and qnrD1. Some resistance genes were closely linked in resistance gene cassettes with either transposases in close proximity or situated on putative mobile elements or predicted plasmids. Single-nucleotide polymorphism genotyping revealed large genetic variation between the G. anatis isolates, including isolates retrieved from the same farm. G. anatis might play a hitherto unrecognized role as a respiratory pathogen and resistance gene reservoir in cattle and has unknown zoonotic potential.

Gallibacterium anatis是一种机会性病原体，以前与家禽、家禽和偶尔人类的死亡有关。我们从 10 只对抗菌药物治疗无反应的支气管肺炎小牛的支气管肺泡灌洗液样本中获得了G. anatis分离株。收集的分离株对广泛耐药具有多重耐药性，对 5-7 类抗菌药物表现出耐药性。全基因组测序揭示了 24 种不同的抗菌素耐药性决定因素，包括以前未在鸡杆菌属甚至巴氏杆菌科中描述的基因，例如aad A23、bla _CARB-8、tet (Y) 和qnr D1。一些抗性基因在抗性基因盒中与靠近或位于推定的移动元件或预测质粒上的转座酶密切相关。单核苷酸多态性基因分型揭示了G. anatis分离株之间的巨大遗传变异，包括从同一农场检索到的分离株。G. anatis可能作为牛的呼吸道病原体和抗性基因库发挥迄今为止未被认识的作用，并且具有未知的人畜共患潜力。