UPDATE ON NEW TESTS FROM
THE BACTERIOLOGY LABORATORIES AT ADDL
New antibiotic sensitivity panels for bovine and porcine
isolates
Effective August 21, 2000 and in addition to our existing
antimicrobial sensitivity break point (BK) panels (Table 1)
for food animals (mainly bovine and porcine), the bacteriology
laboratory will be offering a new panel (Table 2) which will
provide minimum inhibitory concentrations (MIC). The cost
for sensitivity tests remains the same if only one panel is
tested for each isolate. Please indicate on your submission
form if you wish to test your isolates against the MIC or
BK panel. If not indicated, the BK panel will be used. As
you will notice, the new panel has replaced tetracycline (TC)
with chlortetracycline (CTC) or oxytetra-cycline (OTC). This
change is based on recent data indicating that there are poor
correlations between in vitro efficacy of TC and that
of CTC or OTC. Since TC has not been effective and there
are limited spaces on the plates, TC was removed from the
panel. In addition, more sulfa drugs have been added to the
new panel while amikacin, novobiocin, cephalothin and sarafloxicin
were removed. The new panel will allow veterinarians to
choose the most effective and economic antibiotics.
Table 1 (Break Point)
Antibiotic
|
Concentration range (ug/ml)
|
Amikacin
|
16,32
|
Florfenicol
|
0,5,1
|
Apramycin
|
8,16
|
Novobiocin
|
4
|
Penicillin
|
0.03,0,12,2
|
Cephalothin
|
8,16
|
Tilmicosin
|
8,16
|
Clindamycin
|
0.5,2
|
Enrofloxacin
|
0.5,1
|
Erythromycin
|
0.5,4
|
Gentamicin
|
4,8
|
Oxacillin+2% Nacl
|
2,4
|
Ampicillin
|
0.25,2,4,8
|
Spectinomycin
|
8,16
|
Sulphachloropyridazine
|
20,40
|
Sarafloxacin
|
0.06,0.12
|
Tetracycline
|
4,8
|
Tiamulin
|
8,16
|
Trimethroprim/Sulphadiazine
|
0.5/9.5,2/38
|
Tylosin
|
5,10
|
Ceftiofur
|
1,2,4
|
Neomycin
|
8
|
Table 2 (MIC)
Antibiotic
|
Concentration range (ug/ml)
|
Ceftiofur
|
0.5,8
|
Erythromycin
|
0.25-4
|
Chlortetracycline
|
0.5-8
|
Florfenicol
|
0.25-8
|
Penicillin
|
0.12-8
|
Ampicillin
|
0.25-16
|
Apramycin
|
4-32
|
Sulphadimethoxine
|
32-256
|
Neomycin
|
4-32
|
Sulphachloropyridazine
|
32-256
|
Tylosin Tartrate
|
2.5-20
|
Sulphathiazole
|
32-256
|
Spectinomycin
|
8-64
|
Tilmicosin
|
4-32
|
Clindamycin
|
0.25-2
|
Tiamulin
|
4-32
|
Enrofloxacin
|
0.12-2
|
Gentamicin
|
1-8
|
Trimethroprim/Sulphamethoxazole
|
0.5/9.5,2/38
|
Oxytetracycline
|
0.25-8
|
|