Antimicrobial susceptibility of Klebsiella spp. and Proteus spp. from various organ systems of horses, dogs and cats as determined in the BfT-GermVet monitoring program 2004-2006.

This research studied the resistance of Klebsiella and Proteus bacteria, collected from various organ systems of horses, dogs, and cats, to different antimicrobial agents, in order to better understand antimicrobial susceptibility.

Understanding the Study

• The research involved 120 bacterial isolates from Klebsiella and Proteus species collected from horses and small animals like dogs and cats.
• The collected Klebsiella strains were mainly from infections of the genital tract (GT) of horses and the urinary/genital tract (UGT) of dogs and cats. For Proteus species, strains were collected from small animal infections of the UGT, skin, ear, and mouth.

Results for Klebsiella spp.

• The study found that these bacteria were most frequently resistant to ampicillin (by 53-67%), sulfamethoxazole (by 19-29%), and potentiated sulfonamides (like the trimethoprim/sulfamethoxazole 1/19 combination) (19-24%).
• Interesting, around 29% of Klebsiella isolates from the UGT of dogs and cats were resistant to an antibiotic called enrofloxacin. However, no isolates from horses showed comparable resistance to this antimicrobial agent.

Results for Proteus spp.

• In Proteus species, the dominant resistance was against tetracycline, with 90-92% of them showing resistance. The reason for this high level of resistance is often attributed to drug efflux proteins, a phenomenon well-documented in scientific literature.
• Furthermore, relevant resistance percentages were also observed for potentiated sulfonamides (27-37%), sulfamethoxazole (24-37%), and chloramphenicol (24-37%).

Overall Significance of the Study

• The research is critical because antimicrobial resistance is a significant global threat. Understanding which bacteria are resistant to which drugs is crucial for deciding the most effective treatments in veterinary medicine.
• Identifying resistance trends also provides important insights into the likely future progression of antimicrobial resistance, ultimately leading to more informed intervention strategies.