Florfenicol Resistance in Enterobacteriaceae and Whole-Genome Sequence Analysis of Florfenicol-Resistant Leclercia adecarboxylata Strain R25

Table 3

Prevalence and antibiotic resistance of Enterobacteriaceae isolated from animal feces from animal farms in South China.

Genera	Isolates	Resistance^a						Resistance genes
		Florfenicol^b			Chloramphenicol			floR	cfr	pexA	fexA	fexB	optrA	estDL136
		S	I	R	S	I	R
Escherichia	251 (86.0%)	87 (34.7%)	7 (2.8%)	157 (62.5%)	84 (33.5%)	6 (2.4%)	161 (64.1%)	164 (65.3%)	0	0	0	0	0	0
Klebsiella	8 (2.7%)	2 (25.0%)	0	6 (75.0%)	0	0	8 (100.0%)	6 (75.0%)	0	0	0	0	0	0
Proteus	9 (3.1%)	1 (11.1%)	0	8 (88.9%)	0	0	9 (100.0%)	8 (88.9%)	3 (1.0%)	0	0	0	0	0
Enterobacter	10 (3.4%)	7 (70.0%)	1 (10.0%)	2 (20.0%)	8 (80.0%)	0	2 (20.0%)	3 (30.0%)	0	0	0	0	0	0
Other genera^c	14 (4.8%)	7 (50.0%)	0	7 (50.0%)	4 (28.6%)	0	10 (71.4%)	7 (50.0%)	0	0	0	0	0	0
Total	292 (100.0%)	104 (35.6%)	8 (2.7%)	180 (61.6%)	96 (32.9%)	6 (2.1%)	190 (65.1%)	188 (64.4%)	3 (1.0%)	0	0	0	0	0

Abbreviations: S: sensitive; I: intermediate; R: resistance. ^aCriteria as published by CLSI 2017. ^bUsing chloramphenicol breakpoints. ^cOther genera of Enterobacteriaceae bacteria including 2 Shigella, 1 Serratia, 5 Citrobacter, 1 Yersinia, 1 Leclercia, 3 Pantoea, and 1 Kluyvera.