Antimicrobial practices for Mycoplasma infections in cattle: A survey of veterinary practitioners in light of current scientific evidence and national guidelines

Abstract

Mycoplasmas are major pathogens in cattle, causing respiratory disease, mastitis and arthritis, and leading to significant economic losses. These pathogens’ microbial characteristics complicate diagnosis, treatment, and the performance of certain laboratory assays such as antimicrobial susceptibility testing (AST). Based on a dedicated survey, this study is the first international investigation of diagnostic and treatment strategies used by cattle veterinarians to manage mycoplasma infections. It also assesses how closely these practices align with current scientific evidence and regulatory recommendations. The survey was led by the MyMIC consortium, whose primary objective is to standardize AST methods for livestock mycoplasmas. The survey collected 270 responses from cattle veterinarians across 40 countries worldwide. PCR was the most commonly used diagnostic method, while culture and AST were performed less frequently. Macrolides, florfenicol and tetracyclines were the preferred antimicrobials, in line with current guidelines. However, some prescription practices deviated from recommendations, including the use of ineffective antimicrobial classes (e.g., beta-lactams and trimethoprim/sulfonamides) or of critically important antimicrobial classes as well as inappropriate dosing or duration regimens. These findings emphasize the need for coordinated actions at multiple levels: promoting the use of AST by veterinarians, disseminating updated diagnostic and treatment recommendations, and developing standardized guidelines and procedures for AST in livestock mycoplasmas. The MyMIC consortium has established an inventory of veterinary strategies for antimicrobial use and diagnosis, including resistance surveillance, thereby contributing to improved antimicrobial stewardship and to the health of livestock systems affected by mycoplasmoses. Continued support of this initiative is strongly recommended.