tetracycline and sulfadiazine--trimethoprim-drug-combination

Minimal inhibition concentration (MIC) values of 100 Finnish and 100 Israeli Escherichia coli isolated from clinical bovine mastitis were determined for ampicillin, cephalexin, ceftazidime, dihydrostreptomycin, gentamicin, tetracycline, trimethoprim-sulfadiazine, and ciprofloxacin by an agar dilution method. The in vitro antimicrobial susceptibility of the E. coli isolates was high; only 27% showed resistance to one or more tested antimicrobial agents. Fifteen percent of the Israeli isolates and 14% of the Finnish isolates were resistant to tetracycline, 3 and 16% to cephalexin, 10 and 7% to ampicillin, 13 and 9% to dihydrostreptomycin, and 4 and 2% to trimethoprim-sulfadiazine. No gentamicin-, ceftazidime-, or ciprofloxacin-resistant isolates were detected. Eleven percent of all the isolates were resistant to two or more antimicrobial agents. Tetracycline was most often associated with multiresistant patterns. Most of the multiresistant isolates had very high MIC values, whereas most of those that were resistant to only one tested antibiotic had MIC values close to the susceptibility breakpoint. Antimicrobial resistance appeared to pose no problem in E. coli isolated from mastitic milk of both countries. This is probably due to the controlled use of antimicrobial agents in the treatment of dairy herds. Some differences were present in the resistance patterns, which may reflect the different use of antimicrobial agents in these two countries.

Topics: Ampicillin; Animals; Anti-Bacterial Agents; Cattle; Ceftazidime; Cephalexin; Ciprofloxacin; Dihydrostreptomycin Sulfate; Drug Combinations; Drug Resistance, Microbial; Escherichia coli; Female; Finland; Gentamicins; Israel; Mastitis, Bovine; Microbial Sensitivity Tests; Sulfadiazine; Tetracycline; Trimethoprim

Topics: Amoxicillin; Amoxicillin-Potassium Clavulanate Combination; Animals; Clavulanic Acids; Diarrhea; Drug Combinations; Drug Therapy, Combination; Escherichia coli; Escherichia coli Infections; Injections, Intramuscular; Remission Induction; Sulfadiazine; Swine; Swine Diseases; Tetracycline; Time Factors; Trimethoprim

Bitches with naturally occurring Brucella canis infection were treated with combined antibiotic therapy consisting of tetracycline, dihydrostreptomycin, and trimethoprim-sulfadiazine. After treatment, all but 1 bitch became abacteremic, and serologic titers declined for a variable length of time (3 months to 1 years). Abortion did not occur while these bitches were abacteremic. Although sequential antibiotic therapy for 6 weeks did not eradicate Brucella canis from affected bitches, it did not prevent abortion. The number of live pups whelped and weaned by treated bitches was comparable with that in bitches before they became infected.

Topics: Abortion, Septic; Abortion, Veterinary; Animals; Brucellosis; Dihydrostreptomycin Sulfate; Dog Diseases; Dogs; Drug Combinations; Drug Therapy, Combination; Estrus; Female; Pregnancy; Pregnancy Complications, Infectious; Sepsis; Sulfadiazine; Tetracycline; Trimethoprim