Mininal Inhibitory Concentrations of commonly used antibiotics for treatment of common veterinary pathogens - a multicenter study in Germany Part II:Staphylococcus aureus und Staphylococcus intermedius strains

A study was carried out in which resistance of veterinary pathogens to 16 a ntibiotics was measured quantitatively. MIC was determined for 125 Staphylo coccus aureus isolates from the bovine udder and for 121 Staphylococcus int ermedius isolates from dogs and cats. The isolates had been cultured in 199 9 in 14 and 9 veterinary laboratories in 8 and 5 German counties, respectiv ely and were then sent to the BgVV. At the same time an agar-diffusion test was performed to determine the inhibition radius (IR). MIC and IR were eva luated according to maximum values taken mostly from DIN 58 940 and integra ted into veterinary proceedings for determination of resistance of rapidly growing bacteria. No resistance to oxacillin and cefoperazone could be dete cted in Staphylococcus aureus from the bovine udder. However, there were re sistances against benzylic penicillin (35.3 %), ampicillin (26.3 %), gentam icin (2.4 %), neomycin (3.2 %), tetracycline (7.2 %), erythromycin(7.1 %), tylosin (11.6 %), lincomycin (8.8 %), and trimethoprim/sulfamethoxazole (3. 2 %). In the isolates of Staphylococcus intermedius, no resistance to genta micin was observed. There were resistances, however, to benzylic penicillin (63.8 %), ampicillin (59.8), tetracycline (47.9 %), erythromycin (30.2 %), tylosin (27.4 %), lincomycin (18.5 %), enrofloxacin (5.1 %), trimethoprim/ sulfamethoxasol (5.0 %), and cephalosporins (3rd generation) (1.7 %). It is pointed out that multifold resistance of pathogens are important in view o f directed therapy.