Table 2.

MIC₅₀ and MIC₉₀ for S. enterica (n = 89) and E. coli (n = 91) isolates.

Antibiotic	S. enterica				E. coli
	Food animals				Food animals (n = 32)	Zoo Animals (n = 23)	Companion Animals (n = 36)
	Breeders (n = 12)	Broilers (n = 33)	Layers (n = 33)	Othersa(n = 11)
Na
MIC50	128	128	128	128	8	4	4
MIC90	128	128	128	128	128	128	128
% Wt	0	12	6	18	59	77	78
%N-Wt	100	88	94	82	41	23	22
Cp
MIC50	0.25	0.25	0.25	0.25	0.03	0.015	0.015
MIC90	0.25	0.25	0.25	0.5	8	8	8
% Wt	0	3	18	36	59	77	72
%N-Wt	100	97	82	64	41	23	28
A
MIC50	2	4	0.5	8	8	8	8
MIC90	4	4	8	64	64	64	64
% Wt	100	100	94	64	53	50	53
%N-Wt	0	0	6	36	47	50	47
Ct
MIC50	0.125	0.06	0.125	0.125	≤ 0.06	0.06	≤ 0.06
MIC90	0.125	0.125	0.125	2	0.125	0.125	0.125
% Wt	100	100	94	82	100	95	94
%N-Wt	0	0	6	18	0	5	6
G
MIC50	0.25	0.25	0.25	0.5	0.5	0.5	0.5
MIC90	0.5	0.5	0.5	1	2	1	1
% Wt	100	100	100	100	91	91	100
%N-Wt	0	0	0	0	9	9	0
St
MIC50	2	2	4	32	4	4	4
MIC90	8	4	128	64	256	256	128
% Wt	100	100	82	36	69	64	86
%N-Wt	0	0	18	64	31	36	14
T
MIC50	2	2	2	4	32	2	2
MIC90	4	4	4	64	64	64	64
% Wt	92	100	91	55	47	59	75
%N-Wt	8	0	9	45	53	41	25
C
MIC50	8	4	8	8	4	8	8
MIC90	8	8	8	16	64	8	16
% Wt	100	97	100	91	84	100	92
%N-Wt	0	3	0	9	16	0	8
Su
MIC50	128	128	128	128	16	32	16
MIC90	128	128	128	>512	>512	>512	>512
% Wt	92	100	100	64	63	59	78
%N-Wt	8	0	0	36	38	41	22
Tp
MIC50	0.5	0.5	0.5	0.25	0.5	0.5	0.5
MIC90	0.5	0.5	0.5	32	32	32	32
% Wt	92	100	100	73	81	68	81
%N-Wt	8	0	0	27	19	32	19

^aOthers, pigs (n = 6) and food products of animal origin (n = 5).

Na, nalidixic acid; Cp, ciprofloxacin; A, ampicillin; Ct, cefotaxime; G, gentamicin; St, streptomycin; T, tetracycline; C, chloramphenicol; Su, sulfamethoxazole; Tp, trimethoprim.