Antimicrobial resistance profile and prevalence of extended-spectrum beta-lactamases (ESBL), AmpC beta-lactamases and colistin resistance (mcr) genes in Escherichia coli from swine between 1999 and 2018

Table 1 Concentrations and breakpoints of the antibiotic disks used for the disk diffusion method

Antibiotic^a	Concentration (μg/mg)	Breakpoint (mm)		Reference^b
Antibiotic^a	Concentration (μg/mg)	S	R	Reference^b
Amoxicillin	25	≥ 17	≤ 13	CLSI M100; human [5]
Amoxicillin - clavulanic	30	≥ 18	≤ 13	CLSI M100; human [5]
Ceftiofur	30	≥ 21	≤ 17	CLSI VET08; cattle E. coli and swine Salmonella cholerasuis [6]
Colistin	50	≥ 15	< 15	CA-SFM; veterinary [7]
Enrofloxacin	5	≥ 23	≤ 16	CLSI VET08; dog, cat and poultry [6]
Gentamicin	10	≥ 16	≤ 12	CLSI VET08; dog, horse [6]
Tetracycline	30	≥ 15	≤ 11	CLSI M100; human [5]

^aAntibiotic disks: BBL™ brand. ^bCLSI veterinary breakpoints were preferably used. If not available, CLSI human or CA-SFM veterinary breakpoints were used

ISSN: 2055-5660