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Antibiotics (Basel, Switzerland)2025; 14(9); 953; doi: 10.3390/antibiotics14090953

Antibiotic Use in Horses: Analysis of 57 German Veterinary Practices (2018-2023).

Abstract: : A mandatory monitoring of the use of antibiotics in horses in the European Union will come into force from 2027 on. The aim of the study was to explore the potential implementation of a monitoring system and to provide an overview of antibiotic use in horses in Germany. : Data on all consultations from 57 German practices between 2018 and 2023 were obtained. The dataset included basic data about the horse, free-text diagnoses (allocated to one of 20 categories), and treatments. Information on the administered or dispensed pharmaceutical product was recorded for antibiotic treatment consultations. : This study analyzed 225,622 consultations with more than 50,000 horses. Antibiotics were administered in around 7% of consultations, but practice-specific rates varied considerably. Treatment was most frequent in ophthalmology cases. The most commonly used drug classes were sulfonamides combined with trimethoprim and aminopenicillins. Horses receiving antibiotics required follow-up visits more often than untreated animals, and changes in antibiotic substance occurred occasionally. : Routine practice data provide valuable insights into antibiotic use in equine medicine. While incomplete entries and imprecise details (e.g., missing concentrations or diagnoses) remain a limitation, the approach offers clear advantages: it is cost-effective, allows large-scale data collection, and supports continuous monitoring over time. Such systems can be used to evaluate the effects of upcoming EU regulations and to identify priorities for antibiotic stewardship in equine practice.
Publication Date: 2025-09-19 PubMed ID: 41009931PubMed Central: PMC12466689DOI: 10.3390/antibiotics14090953Google Scholar: Lookup
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  • Journal Article

Summary

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Overview

  • This study analyzed antibiotic use in horses across 57 German veterinary practices from 2018 to 2023 to assess patterns of use and explore the feasibility of a monitoring system in anticipation of upcoming EU regulations.
  • It provides insights into how frequently antibiotics are used, which drugs are most common, and highlights variability between practices, offering important information to guide antibiotic stewardship efforts.

Purpose and Background

  • The European Union will mandate monitoring antibiotic use in horses starting in 2027 to combat antibiotic resistance.
  • The study aimed to understand how such a monitoring system might be implemented effectively in Germany by analyzing real-world veterinary consultation data.
  • It also aimed to create an overview of current antibiotic usage patterns in equine medicine to inform future regulations and stewardship priorities.

Data Collection and Methodology

  • Data were collected from 57 veterinary practices across Germany spanning January 2018 to mid-2023.
  • The dataset included:
    • Basic horse information (such as identification and potentially age or breed).
    • Free-text diagnoses from consultations, which were categorized into 20 diagnostic groups.
    • Treatment details including what pharmaceutical products were administered or dispensed, focusing particularly on antibiotics.
  • A total of 225,622 veterinary consultations involving over 50,000 horses were analyzed, providing a large-scale, real-world dataset.

Key Findings

  • Antibiotics were used in approximately 7% of all consultations, though there was significant variation in antibiotic use rates across individual veterinary practices.
  • The highest frequency of antibiotic treatment was found in cases related to ophthalmology, indicating eye infections are a common reason for antibiotic use in horses.
  • The most commonly administered antibiotic classes were:
    • Sulfonamides combined with trimethoprim (a commonly used broad-spectrum antibiotic combination).
    • Aminopenicillins (beta-lactam antibiotics effective against many bacteria).
  • Horses treated with antibiotics often required more follow-up visits compared to untreated horses, suggesting either more severe illness or need for treatment adjustments.
  • In some cases, changes were made to the prescribed antibiotic substances during treatment, indicating adjustments possibly due to response or side effects.

Implications and Benefits of the Monitoring Approach

  • Utilizing routine practice data for antibiotic monitoring is cost-effective and can support wide-scale and long-term data collection across many practices.
  • The approach allows for continuous surveillance to identify trends in antibiotic usage patterns in equine veterinary medicine.
  • Such data can help evaluate the impact of forthcoming EU regulations on antibiotic use in horses.
  • Data can also guide targeted antibiotic stewardship interventions to reduce inappropriate use and combat antibiotic resistance.

Limitations

  • Incomplete or imprecise data entries were noted, including missing concentrations of antibiotics or less specific diagnostic information.
  • Free-text diagnoses required categorization, which could introduce some variability in classification accuracy.
  • The analysis focused on data from recorded treatments only and may miss treatments administered outside of the documented consultations.

Conclusions

  • The study demonstrates that monitoring antibiotic use through routine veterinary practice data is feasible and valuable for understanding equine antibiotic prescribing behavior.
  • There is considerable variability in antibiotic use between practices, highlighting opportunities for harmonization and stewardship.
  • The findings support the development of monitoring systems ahead of EU mandates and provide key data to inform efforts aimed at responsible antibiotic use in horse medicine.

Cite This Article

APA
Merle R, Feuer L, Frenzer K, Plenio JL, Bethe A, Sarnino N, Lübke-Becker A, Bäumer W. (2025). Antibiotic Use in Horses: Analysis of 57 German Veterinary Practices (2018-2023). Antibiotics (Basel), 14(9), 953. https://doi.org/10.3390/antibiotics14090953

Publication

ISSN: 2079-6382
NlmUniqueID: 101637404
Country: Switzerland
Language: English
Volume: 14
Issue: 9
PII: 953

Researcher Affiliations

Merle, Roswitha
  • Institute of Veterinary Epidemiology and Biostatistics, Veterinary Centre for Resistance Research, Freie Universität Berlin, 14163 Berlin, Germany.
Feuer, Leonie
  • Institute of Pharmacology and Toxicology, Freie Universität Berlin, 14195 Berlin, Germany.
Frenzer, Katharina
  • Institute of Veterinary Epidemiology and Biostatistics, Veterinary Centre for Resistance Research, Freie Universität Berlin, 14163 Berlin, Germany.
Plenio, Jan-Lukas
  • Institute of Veterinary Epidemiology and Biostatistics, Veterinary Centre for Resistance Research, Freie Universität Berlin, 14163 Berlin, Germany.
Bethe, Astrid
  • Institute of Microbiology and Epizootics, Veterinary Centre for Resistance Research, Freie Universität Berlin, 14163 Berlin, Germany.
  • German Environment Agency, Wörlitzer Platz 1, 06844 Dessau-Roßlau, Germany.
Sarnino, Nunzio
  • Institute of Veterinary Epidemiology and Biostatistics, Veterinary Centre for Resistance Research, Freie Universität Berlin, 14163 Berlin, Germany.
Lübke-Becker, Antina
  • Institute of Microbiology and Epizootics, Veterinary Centre for Resistance Research, Freie Universität Berlin, 14163 Berlin, Germany.
Bäumer, Wolfgang
  • Institute of Pharmacology and Toxicology, Freie Universität Berlin, 14195 Berlin, Germany.

Grant Funding

  • 2820HS002 / German Federal Office for Agriculture and Food

Conflict of Interest Statement

The authors declare no conflicts of interest.

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