Molecular Epidemiology of Klebsiella pneumoniae from Clinical Bovine Mastitis in Northern Area of China, 2018–2019
Shikai Song,
Wenjuan He,
Dawei Yang,
Manar Benmouffok,
Yao Wang,
Jiyun Li,
Chengtao Sun,
Xiangbin Song,
Shizhen Ma,
Chang Cai,
Shuangyang Ding,
Congming Wu,
Zhangqi Shen,
Yang Wang
Affiliations
Shikai Song
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Wenjuan He
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Dawei Yang
China Institute of Veterinary Drug Control, Beijing 100081, China
Manar Benmouffok
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Yao Wang
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Jiyun Li
College of Veterinary Medicine, Hunan Agricultural University, Changsha 410125, China
Chengtao Sun
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Xiangbin Song
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Shizhen Ma
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Chang Cai
Research and Innovation Office, Murdoch University, Murdoch 6150, Australia; China Australia Joint Laboratory for Animal Health Big Data Analytics, College of Animal Science and Technology, Zhejiang Agricultural and Forestry University, Hangzhou 311300, China
Shuangyang Ding
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Congming Wu
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Zhangqi Shen
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
Yang Wang
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China; Corresponding author.
Klebsiella pneumoniae (K. pneumonia, KpI) is a predominate inducement of bovine mastitis, which is associated with high mortality and milk yield reduction. However, data is lacking on the molecular characteristics of bovine K. pneumoniae, limiting the risk assessment of its transmission through the food chain. Herein, we investigated the prevalence of K. pneumoniae in 6301 clinical mastitis (CM) milk samples from dairy cattle in northern area of China. In total, 183 K. pneumoniae isolates were recovered, with detection rates of 3.0% and 2.8% in 2018 and 2019, respectively. Like human clinical K. pneumoniae, all CM K. pneumoniae isolates belonged to one of three phylogroups: KpI (n = 143), Klebsiella. quasipneumoniae subsp. similipneumoniae (KpII-B) (n = 37), and Klebsiella variicola (KpIII) (n = 3). We detected the extended-spectrum β-lactamase-encoding genes blaSHV-2a, blaCTX-M-14, and blaCTX-M-15, as well as clpC, lpfA, lacI, lacZ, lacY, and the fecABDEIR operon in the KpI isolates, which may contribute to their pathogenicity and host adaptability in cows. The high prevalence of KpI in dairy farms may be problematic, as it showed relatively higher rates of antibiotic resistance and virulence gene carriage than the KpII-B and KpIII isolates. Furthermore, we observed distinct differences in population structure between CM- and human infection-associated KpI isolates, with the genes associated with invasive infection in humans rarely being observed in bovine isolates, indicating that few CM-associated K. pneumoniae isolates pose a threat to human health. Nevertheless, bovine KpII-B isolates shared a high level of nucleotide sequence identity with isolates from human infections and frequently carried the nitrogen-fixation gene nif, suggesting an association between KpII-B isolates from cattle and humans, and plant-derived bacteria.
