. 2017 Oct 6;73(1):57–65. doi: 10.1093/jac/dkx342

Table 2.

Antimicrobial resistance genes located in ICEApl2 and levels of resistance to relevant antimicrobial agents for A. pleuropneumoniae MIDG3553

Antimicrobial resistance gene in ICEApl2	Antimicrobial agent	MIC (mg/L)
dfrA1	trimethoprim	≥1024
sul2	sulfisoxazole	≥1024
strA, strB	streptomycin	256
floR	florfenicol	0.5^a
	chloramphenicol	1^b

Not considered resistant; MICs of florfenicol ≥8 mg/L are considered resistant for A. pleuropneumoniae.²¹

There is no published breakpoint for resistance of A. pleuropneumoniae to chloramphenicol; however, plasmids pM3446F and p518, carrying identical floR genes, both conferred MICs of florfenicol and chloramphenicol of 8 mg/L for their respective A. pleuropneumoniae isolates, MIDG3446 and MV518.²²^,³⁰