Excreted Antibiotics May Be Key to Emergence of Increasingly Efficient Antibiotic Resistance in Food Animal Production

• DOI: 10.1128/aem.00791-22
• Publication Date: 2022-07-14T13:01:50Z
• Authors: Johannetsy J. Avi...; Parvaneh Ahmadvand; Shao-Yeh Lu; Jennifer Horton; Jinxin Liu; Eric Lofgren; Margaret A. Davis; ChulHee Kang; Douglas R. Call
• Keywords: Ceftiofur; Cephalosporin Antibiotic; Cefalotin

We studied the relative fitness benefits of a cephalosporin resistance enzyme (CTX-M-15) that is displacing similar (CMY-2), which extant in E. coli from dairy cattle Washington State. In vitro experiments demonstrated CTX-M-15 provides significant advantage, but only presence very high concentrations antibiotic are found when ampicillin, and to lesser extent ceftiofur, excreted urine treated animals. As such, increasing prevalence bacteria with bla likely occurring ex vivo .