AUTHOR=Bello Gonzalez Teresita d.J. , Kant Arie , Dijkstra Quillan , Marcato Francesca , van Reenen Kees , Veldman Kees T. , Brouwer Michael S. M. 

TITLE=Changes in Fecal Carriage of Extended-Spectrum β-Lactamase Producing Enterobacterales in Dutch Veal Calves by Clonal Spread of Klebsiella pneumoniae

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.866674

DOI=10.3389/fmicb.2022.866674

ISSN=1664-302X

ABSTRACT=<p>This study aimed to characterize the changes in fecal carriage of Extended-Spectrum β-Lactamase (ESBL) producing Enterobacterales (ESBL-PE) in a single Dutch veal calves. During the rearing period at the Dutch veal farm, a decrease in fecal carriage of cefotaxime-resistant <italic>Escherichia coli</italic> isolates was observed after 2 weeks at the veal farm, while an increase of cefotaxime-resistant <italic>Klebsiella pneumoniae</italic> isolates was demonstrated. <italic>E. coli</italic> and <italic>K. pneumoniae</italic> were isolated from rectal swabs collected from 110 veal calves in week 2, 6, 10, 18, and 24 after their arrival at the farm. ESBL-PE isolates were selectively cultured and identified by MALDI-TOF. ESBL genes were characterized by RT-PCR, PCRs, and amplicon sequencing. A total of 80 <italic>E. coli</italic> and 174 <italic>K. pneumoniae</italic> strains were isolated from 104 out of 110 veal calves. The prevalence of ESBL-<italic>E. coli</italic> decreased from week 2 (61%) to week 6 (7%), while an unexpected increase in ESBL-<italic>K. pneumoniae</italic> colonization was detected in week 6 (80%). The predominant ESBL genes detected in <italic>E. coli</italic> isolates were <italic>bla</italic><sub>CTX-M-15</sub> and the non-ESBL gene <italic>bla</italic><sub>TEM-1a</sub>, while in <italic>K. pneumoniae bla</italic><sub>CTX-M-14</sub> gene was detected in all isolates. Four cefotaxime-resistant <italic>K. pneumoniae</italic> isolates were randomly selected and characterized in deep by transformation, PCR-based replicon typing, and whole-genome sequencing (WGS). The clonal relatedness of a subgroup of nine animals carrying <italic>K. pneumoniae</italic> ESBL genes was investigated by Multi Locus sequence typing (MLST). In four ESBL-<italic>K. pneumoniae</italic> isolates, <italic>bla</italic><sub>CTX-M-14</sub> was located on IncFII<sub>K</sub> and IncFII<sub>NK</sub> plasmid replicons and the isolates were multi-drug resistant (MDR). MLST demonstrated a clonal spread of ESBL-<italic>K. pneumoniae</italic> ST107. To the best of our knowledge, this is the first study to report a change in fecal carriage of ESBL-PE over time in the same veal calf during the rearing period.</p>