Genetic characterization of virulence and extended spectrum β-lactamase producing genes of Klebsiella pneumoniae isolated from bovine milk

Mastitis associated Klebsiella pneumoniae species were isolated from bovine milk to characterize virulence genes (wabG and kfuBC) and extended spectrum β-lactamase (ESBL) genes (blaCTX-M-۱, blaCTX-M-۲, blaCTX-M-۹, blaTEM, blaSHV and blaOXA). A total number of ۳۲۵ bovine milk samples (۱۹۵ raw and ۱۳۰ mastitic milk specimens) collected from Banaskantha, a milk-shed district of Gujarat, India, were included in the study. A total number of ۲۷ K. pneumoniae isolates were recovered, consisting of ۱۷ (۶۲.۹۶%) isolates from raw milk and ۱۰ (۳۷.۰۳%) isolates from mastitic milk samples, giving an overall prevalence of ۸.۳۱%. Antibiotic sensitivity patterns revealed that ۲۰ out of ۲۷ isolates were found to be multi-drug resistant. Based on combination disc diffusion test and HiCrome ESBL agar method, ۲۰ (۷۴.۰۷%) and ۲۵ (۹۲.۵۹%) isolates were detected as ESBL producers, respectively. Among virulence genes studied, presence of wabG (۲۵/۲۷; ۹۲.۵۹%) was higher than kfuBC (۵/۲۷; ۱۸.۵۱%). Beta-lactamase genes viz., blaSHV, blaTEM and blaCTX-M-۱ were detected in ۲۳/۲۷ (۸۵.۱۸%), ۳/۲۷ (۱۱.۱۱%) and ۲/۲۷ (۷.۴۰%) of isolates, respectively; while, none of the isolates was found to be positive for blaCTX-M-۹ and blaOXA-۱ genes. Outcome of the study provided an insight into virulence genes and ESBL producing K. pneumoniae isolated from bovine milk samples in India.

کلیدواژه ها:

Bovine mastitis ، Drug resistance ، India ، Klebsiella pneumoniae ، Virulence Factors