Antimicrobial resistance of Pasteurella multocida type B isolates associated with acute septicemia in pigs and cattle in Spain

Table 2 MIC value distribution of Pasteurella multocida type B isolates derived from swine (n = 58)

Break point	Ab	Number of isolates for each MIC (μg/mL)										MIC₅₀	MIC₉₀	%R
Break point	Ab	≤0.03	0.06	0.125	0.25	0.5	1	2	4	8	≥16	MIC₅₀	MIC₉₀	%R
≥1	ENR	45	2	2	1	4	3	0	1	0	0	≤0.03	0.5	6.9
≥8	CEF	39	3	0	1	4	7	3	1	0	0	≤0.03	1	0
> 8	GEN	0	0	0	0	0	3	11	16	19	9	4	≥16	15.5
≥32	C	0	0	0	2	29	6	3	3	4	>11^c	0.5	≥16	17.2
> 2	LIN	0	0	0	0	0	0	0	0	6	52	≥16	≥16	100
≥1	PEN	10	12	17	3	0	0	16	0	0	0	0.125	2	27.6
≥2^a	OXY	4	3	6	26	6	1	2	1	9	0	0.25	8	20.7
≥2	TE	3	0	6	16	9	7	7	3	7	0	0.5	8	29.3
ND	ERY	0	0	2	2	3	8	1	8	0	34	≥16	≥16	ND
ND^b	NEO	0	0	0	0	0	1	6	14	20	17	8	≥16	ND

^a breakpoint reference value for tetracycline; ^b breakpoint value for P. multocida derived from dogs; ^c MIC value = 32 μg/mL. Ab Antibiotic; C Chloramphenicol; CEF Ceftiofur; ENR Enrofloxacin; ERY Erythromycin; GEN Gentamicin; LIN Lincomycin; MIC Minimum inhibitory concentration; ND Non-determined value for P. multocida according to the Clinical and Laboratory Standards Institute (CLSI; 2013); NEO Neomycin; OXY Oxytetracycline; PEN Penicillin; TE Tetracycline

ISSN: 1746-6148