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The Canadian veterinary journal = La revue veterinaire canadienne2025; 66(8); 903-910;

Evolution of in vitro antimicrobial resistance at an equine hospital over 4 decades.

Abstract: This study aimed to document antimicrobial resistance patterns of bacteria frequently isolated at a referral equine hospital between 2020 and 2022 and to compare these results to those of studies carried out in previous decades at the same reference center. Unassigned: Using the Kirby-Bauer method, 340 tests were completed on bacterial isolates and compared to 233, 255, and 396 tests carried out in 1986 to 1988, 1996 to 1998, and 2007 to 2013, respectively. Data were analyzed with tests for trends, followed by pairwise Fisher tests and Bonferroni corrections. Unassigned: Increasing resistance to at least 1 antibiotic was observed for 5 of the 6 bacteria studied, including increasing resistance to enrofloxacin for spp., spp., and staphylococci, and to ceftiofur for spp. and staphylococci. Resistance of spp. to ampicillin and penicillin decreased over time, whereas resistance of subsp. to penicillin was not observed. Unassigned: Bacteria isolated from horses had increasing resistance to antibiotic classes considered critically important for human health. However, penicillin remained an appropriate 1st-line antibiotic for spp. and subsp. in our area. Évolution de la résistance aux antibiotiques dans un hôpital équin sur 4 décennies. Unassigned: Cette étude documente la résistance de bactéries isolées dans un hôpital équin entre 2020 et 2022, et la compare avec des études réalisées lors des précédentes décennies dans le même hôpital. Unassigned: Par la méthode de Kirby-Bauer, 340 tests ont été réalisés et ont été comparés aux 233, 255 et 396 tests réalisés en 1986–1988, 1996–1998 et 2007–2013. Les données ont été analysées avec des tests de tendance du chi-carré, des tests de Fisher et des corrections de Bonferroni. Unassigned: Une augmentation de la résistance à au moins un antibiotique a été observée pour 5 des 6 bactéries étudiées, incluant une augmentation de la résistance à l’enrofloxacine pour spp., spp. et les staphylocoques, et au ceftiofur pour spp. et les staphylocoques. Le résistance d’ spp. à l’ampicilline et à la pénicilline a diminué et aucune résistance de subsp. à la pénicilline n’a été observée. Unassigned: Une augmentation de la résistance à des antibiotiques d’importance cruciale pour la santé humaine a été observée. La pénicilline reste un antibiotique de première intention approprié pour spp. et subsp. dans notre région.(Traduit par les auteurs).
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Publication Date: 2025-08-01 PubMed ID: 40786736PubMed Central: PMC12330761
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research discusses the increasing resistance of bacteria found in horses to common antibiotics over a period of four decades at an equine hospital. The study noted an increase in resistance in 5 of the 6 studied bacteria to at least one antibiotic, with only a couple of bacteria showing reduced resistance to certain antibiotics.

Research Methodology

  • The study was conducted at a referral equine hospital where the antimicrobial resistance of isolated bacteria was documented between 2020 to 2022.
  • The researchers used the Kirby-Bauer method to carry out 340 tests on the bacterial isolates.
  • For comparative analysis, they used data from previous tests conducted at the same hospital – 233 tests conducted between 1986 to 1988, 255 tests from 1996 to 1998, and 396 tests from 2007 to 2013.
  • The collected data were analyzed using Chi-square tests for trends, followed by pairwise Fisher tests and Bonferroni corrections.

Findings

  • The research found that 5 out of 6 studied bacteria showed increased resistance to at least one antibiotic.
  • Three types of bacteria displayed increased resistance to Enrofloxacin, and two types showed increased resistance to Ceftiofur.
  • Interestingly, the resistance of one type of bacteria to Ampicillin and Penicillin decreased over time, while another bacteria subtype didn’t show any resistance to Penicillin.

Implication and Conclusion

  • The increasing antimicrobial resistance observed in the study poses a serious concern for human health, as the resistant bacteria may transfer to humans and pose potential health risks.
  • The study produced crucial insights into the decision-making regarding the use of antibiotics for treatment. For instance, despite the overall trend of increasing antibacterial resistance, Penicillin remained an effective antibiotic for some bacteria during the study period, suggesting it can still be a first-line treatment.

Cite This Article

APA
Symoens A, Gauthier ML, Paillette L, Allano M, Lavoie JP, Leclère M. (2025). Evolution of in vitro antimicrobial resistance at an equine hospital over 4 decades. Can Vet J, 66(8), 903-910.

Publication

The Canadian veterinary journal = La revue veterinaire canadienne
ISSN: 2819-4403
NlmUniqueID: 0004653
Country: Canada
Language: English
Volume: 66
Issue: 8
Pages: 903-910

Researcher Affiliations

Symoens, Antoine
  • Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, 3200, rue Sicotte, Saint-Hyacinthe (Québec) J2S 7C6 (Symoens, Paillette, Allano, Lavoie, Leclère); Centre de diagnostic vétérinaire de l'Université de Montréal (CDVUM), 3220, rue Sicotte, Saint-Hyacinthe (Québec) J2S 2M2 (Gauthier).
Gauthier, Marie-Lou
  • Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, 3200, rue Sicotte, Saint-Hyacinthe (Québec) J2S 7C6 (Symoens, Paillette, Allano, Lavoie, Leclère); Centre de diagnostic vétérinaire de l'Université de Montréal (CDVUM), 3220, rue Sicotte, Saint-Hyacinthe (Québec) J2S 2M2 (Gauthier).
Paillette, Louise
  • Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, 3200, rue Sicotte, Saint-Hyacinthe (Québec) J2S 7C6 (Symoens, Paillette, Allano, Lavoie, Leclère); Centre de diagnostic vétérinaire de l'Université de Montréal (CDVUM), 3220, rue Sicotte, Saint-Hyacinthe (Québec) J2S 2M2 (Gauthier).
Allano, Marion
  • Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, 3200, rue Sicotte, Saint-Hyacinthe (Québec) J2S 7C6 (Symoens, Paillette, Allano, Lavoie, Leclère); Centre de diagnostic vétérinaire de l'Université de Montréal (CDVUM), 3220, rue Sicotte, Saint-Hyacinthe (Québec) J2S 2M2 (Gauthier).
Lavoie, Jean-Pierre
  • Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, 3200, rue Sicotte, Saint-Hyacinthe (Québec) J2S 7C6 (Symoens, Paillette, Allano, Lavoie, Leclère); Centre de diagnostic vétérinaire de l'Université de Montréal (CDVUM), 3220, rue Sicotte, Saint-Hyacinthe (Québec) J2S 2M2 (Gauthier).
Leclère, Mathilde
  • Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, 3200, rue Sicotte, Saint-Hyacinthe (Québec) J2S 7C6 (Symoens, Paillette, Allano, Lavoie, Leclère); Centre de diagnostic vétérinaire de l'Université de Montréal (CDVUM), 3220, rue Sicotte, Saint-Hyacinthe (Québec) J2S 2M2 (Gauthier).

MeSH Terms

  • Animals
  • Horses
  • Anti-Bacterial Agents / pharmacology
  • Hospitals, Animal
  • Drug Resistance, Bacterial
  • Horse Diseases / microbiology
  • Horse Diseases / drug therapy
  • Microbial Sensitivity Tests / veterinary
  • Bacteria / drug effects

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