In recent studies in the UK [?], [?], Australia [?], Sweden [?], USA [?], and the Czech Republic [?], tiamulin has been shown to possess extremely potent activity in vitro against the weakly beta-haemolytic spirochaete, B. pilosicoli. (See Tables below)
| UK |
Ripley, P. (1998) |
| MICs (µg/ml) of various antibiotics for B. pilosicoli |
| Antimicrobial |
Dalziel, R. UK |
Møller, K. Denmark |
| |
MIC range
(n=12) |
MIC50 |
MIC range
(n-5) |
MIC50 |
| Lincomycin |
0.25 - 12.5 |
4.32 |
0.5 - 128.0 |
13.8 |
| Tylosin |
10.0 - >200 |
31.6 |
2.0 - 128.0 |
24.0 |
| Tiamutin® (tiamulin) |
0.031 - 0.5 |
0.067 |
0.0156 - 0.0625 |
0.041 |
|
| AUSTRALIA |
Oxberry, S.L. and Hampson, D.J. (1998) |
| MICs (µg/ml) of various antibiotics for B. pilosicoli (n = 35) |
| Antimicrobial |
MIC50 |
MIC90 |
| Lincomycin |
17 |
47 |
| Tylosin |
>100 |
>100 |
| Tiamutin® (tiamulin) |
<0.1 |
1.5 |
|
| SWEDEN |
Fellström, C. and others (1996) |
| MICs (µg/ml) of various antibiotics for B. pilosicoli |
| Antimicobial |
MIC range |
| Tylosin |
8.0- >16.0 |
| Tiamutin® (tiamulin) |
0.0125 - 0.5 |
|
| USA |
Kinyon, J.M. and others (2002) |
| Sensitivity in vitro (µg/ml) of 25 isolates of B. pilosicoli isolated from 15 pig herds in US/Canada |
| Antimicobial |
MIC range |
MIC50 |
MIC90 |
| Lincomycin |
4- >128 |
32 |
64 |
| Tylosin |
<16 - >512 |
>512 |
>512 |
| Tiamutin® (tiamulin) |
0.06 - 8.0 |
0.125 |
1.0 |
|
| CZECH REPUBLIC |
Cizek, A. and others (2004) |
| MICs of 33 B. pilosicoli strains isolated in the Czech Republic between 1997-1999 and 2001-2003 |
| |
1997-1999 (n=18) |
2001-2003 (n=15) |
Total (n=33) |
| Antimicrobials |
MIC
range |
MIC50
|
MIC90
|
MIC
range |
MIC50
|
MIC90
|
MIC
range |
MIC50
|
MIC90
|
Tiamutin®
(tiamulin) |
0.03-8.0 |
0.125 |
2.0 |
0.03-1.0 |
0.250 |
1.0 |
0.03-8.0 |
0.125 |
1.0 |
| Valnemulin |
0.03-4.0 |
0.125 |
2.0 |
0.03-2.0 |
0.125 |
1.0 |
0.03-4.0 |
0.125 |
2.0 |
| AIVT * |
3.125-200 |
100 |
200 |
3.125-200 |
50 |
200 |
3.125-200 |
50 |
200 |
| Lincomycin |
0.5-128 |
32 |
64 |
0.5-128 |
2.0 |
32 |
0.5-128 |
16 |
64 |
|
| UK |
Vet. Lab. Agency, Winchester (2003)* |
| Sensitivity (µg/ml) in vitro to Tiamutin® (tiamulin) of 10 strains of B. pilosicoli – UK |
| Isolate reference |
MIC (µg/ml) |
| 1. |
24/P 0221-11-02 |
0.031 |
| 2. |
22/P 0039-12-02 |
0.25 |
| 3. |
16/P 0218-06-02 |
0.031 |
| 4. |
22/P 0133-03-03 |
0.015 |
| 5. |
22/P 0012-05-03 |
0.062 |
| 6. |
16/P 0075-10-02 |
0.25 |
| 7. |
15/P 0037-04-03 |
0.062 |
| 8. |
24/P 0250-11-02 |
0.031 |
| 9. |
26/P 0616-03-03 |
0.25 |
| 10. |
16/P 0406-04-03 |
0.5 |
| Mean |
0.148 |
| Reference strain |
0.015 |
|
Colitis and Ileitis often occur simultaneously in chronically affected herds and may impair growth performance. [?] Tiamulin, being highly effective against both B. pilosicoli and L. intracellularis, is particularly useful for treating this dual infection. [?]
| 
