EN
The aim of this study was to determine the in vitro resistance of aerobic bacteria isolated from the uterine pathological secretion of 312 dairy cows with clinical metritis and clinical endometritis to antibiotics. Animals with pathological discharges from the vagina observable between the 7th and 50th day after parturition were diagnosed clinically per vaginam and per rectum and then swabs from uteri lumen were aseptically collected. Bacteriological examinations of swabs were performed according to commonly accepted rules. Sensitivity to antibiotics was tested by the disk diffusion method and performed according to CLSI (formerly NCCLS) guidelines in Mueller-Hinton agar. The bacteria isolated were mostly Arcanobacterium pyogenes, Escherichia coli, non E. coli Gram-negative rods, Streptococcus species and Staphylococcus species. Strains of Arc. pyogenes were the most susceptible to amoxicillin/clavulanic acid (97.3%), ceftiofur (98%) and bacitracine (96.7%). E. coli isolates were the most susceptible to norfloxacin (100%), marbofloxacin (100%), rifaximin (97%), gentamycin (96%) and amoxicillin/clavulanic acid (95.5%). Other Gram-negative bacteria were the most sensitive to norfloxacin (100%), neomycin (100%) and cefoperazon (95%). Streptococcus species were the most susceptible to amoxicillin/clavulanic acid (94.6%), ampicillin (92.3%), norfloxacin (92%), cephapirine (88%), cefoperazone (86.5%), rifaximine (85.7%) and penicillin (84.9%). The highest in vitro activity against Staphylococcus spp. was demonstrated by amoxicillin/clavulanic acid (100%), norfloxacin (100%), neomycin (93.6%) and cefoperazone (85.7%). Arc. pyogenes were the most resistant to oxytetracycline and cloxacillin, E. coli to ampicillin and cephapirin, non-E. coli Gram-negative rods to ampicillin and cephapirin, Streptococcus spp. to neomycin and oxytetracycline, and Staphylococcus spp. to ampicillin.