Antimicrobial Resistance Profile and Genotypic Characteristics of Streptococcus suis Capsular Type 2 Isolated from Clinical Carrier Sows and Diseased Pigs in China
Table 2
Antimicrobial resistance profile of S. suis serotype 2 from clinically healthy carrier sows and diseased pigs.
Antimicrobials
MIC breakpoint* (g/mL)
Healthy carrier sows ()
Diseased pigs ()
Total ()
S
I
R
MIC range
MIC range
MIC range
Penicillin
0.12
0.25–2
4
≤0.06–>8
2
≤0.06–1
0
≤0.06–>8
2
Ampicillin
0.25
0.5–4
8
≤0.12–2
0
≤0.12–0.5
0
≤0.12–2
0
Erythromycin
0.25
0.5
1
0.12–>8
35
≤0.06–4
2
≤0.06–>8
37
Clindamycin
0.5
1-2
4
0.06–>4
35
0.06–>4
2
0.06–>4
37
Enrofloxacin
0.25
0.5–1
2
0.12–>4
6
0.06–1
0
0.06–>4
6
Tetracycline
2
4
8
0.5–>8
57
0.25–>8
28
0.25–>8
85
Ceftiofur
2
4
8
≤0.12–>16
3
≤0.12–2
0
≤0.12–>16
3
Tiamulin
16
—
32
≤0.25–>32
7
≤0.25–16
0
≤0.25–>32
7
Tilmicosin
16
—
32
1–>64
35
≤0.5–64
2
≤0.5–>64
37
Chloramphenicol
4
8
16
≤1–32
3
≤1–8
0
≤1–32
3
Sulfisoxazole
256
—
512
32–>512
46
32–>512
18
32–>512
64
Trimethoprim/ sulfamethoxazole
2/38
—
4/76
≤0.5/9.5–>16/304
13
≤0.5/9.5–16/304
2
≤0.5/9.5–>16/304
15
MIC breakpoints were taken from Clinical and Laboratory Standards Institute standards (CLSI). S: susceptible; I: intermediate; R: resistant. **Number of resistance isolates.
