Resistance patterns of bovine mastitis pathogens in Switzerland
Schifferli, D.; Schällibaum, M.
Schweizer Archiv für Tierheilkunde 126(3): 121-127
1984
ISSN/ISBN: 0036-7281 PMID: 6372088 Document Number: 231742
Bacterial isolates from bovine mastitis cases were tested for resistance to 10 commonly used antibiotics, sulfamethoxazole and trimethoprim. Of 591 streptococcal strains only 78 (13%) showed any resistance, 40 (51.3%) being resistant to tetracycline, 16 (20.5%) to cloxacillin and 19 (about 25%) to 2 and more antibiotics. Of 371 Staphylococcus aureus isolates, 230 (62%) showed resistance, 82% being resistant to penicillin and over 50% exhibiting multiple resistance. Among 374 Escherichia coli isolates, resistance was found in 112 (30%). Almost 90% of the latter were resistant to streptomycin and an equal proportion were multiply-resistant. Resistance to trimethoprim was observed only in strains with multiple resistance. Of 39 strains of enterobacteriaceae other than E. coli, 33 showed some resistance. All of them were resistant to ampicillin, 9 displaying multiple resistance.