Critically important antimicrobials are frequently used on equine racetracks

OBJECTIVE To characterize antimicrobial use on four racetracks in the eastern US during the peak racing 2017-2018 seasons. PROCEDURES Handwritten daily treatment sheets provided by attending veterinarians who listed treatments administered to horses stabled at the racetrack were obtained. Information contained in the treatment sheets included the date, name of the horse and its trainer, type of treatment, and a brief (usually 1-word) indication for treatment. The handwritten data listed on the racetrack treatment sheets were manually transcribed and analyzed. RESULTS A total of 2,684 antimicrobial prescriptions were recorded, representing 6.8% of all drug treatments. The most frequently prescribed antimicrobials were enrofloxacin, with 854 prescriptions (31.8% of antimicrobial treatments), followed by gentamicin (570 [21.2%] prescriptions), ceftiofur (388 [14.5%] prescriptions,), and penicillin (220 [8.2%] prescriptions). The relative frequencies of antimicrobial class and indication for treatment varied significantly by racetrack and by prescribing veterinarian. Limitations associated with the data precluded ascertainment of the proportion of horses treated or exact indications for treatment.

Automated summary

The objective of this study was to investigate antimicrobial use on four racetracks in the eastern US during the peak racing season of 2017-2018. A total of 2,684 antimicrobial prescriptions were recorded, representing 6.8% of all drug treatments. The most commonly prescribed antimicrobials were enrofloxacin, gentamicin, ceftiofur, and penicillin.