Survey of the antimicrobial susceptibility of Escherichia coli isolated from horses admitted to the Western College of Veterinary Medicine, Saskatoon, Saskatchewan.
Abstract: Antimicrobial resistance is a serious threat in human and veterinary medicine. Among the most problematic resistant organisms are the extended-spectrum β-lactamase (ESBL)-producing Enterobacterales, which are resistant to the 3rd-generation cephalosporins. The purpose of this study was to determine the frequency of colonization of horses admitted to the Western College of Veterinary Medicine with resistant Escherichia coli. Unassigned: Rectal swabs were collected from 60 horses admitted between November 2021 and March 2022. Swabs were selectively cultured for E. coli, which was identified using standard biochemical tests. The antimicrobial susceptibility of isolates was determined, and resistant isolates were screened using PCR for the presence of ESBL. Unassigned: Escherichia coli was isolated from all 60 horses. Although pansusceptibility was the most commonly identified phenotype, multidrug-resistant isolates possessing a CTX-M-type ESBL were recovered from 1 horse. Resistance to trimethoprim + sulfamethoxazole was the most commonly encountered resistant phenotype. Unassigned: Although resistance was uncommon, the identification of ESBL-producing isolates highlighted the importance of continued surveillance to monitor the emergence of resistance in equine populations. Étude de la sensibilité aux antimicrobiens d’Escherichia coli isolé chez des chevaux admis au Western College of Veterinary Medicine, Saskatoon, Saskatchewan. Unassigned: La résistance aux antimicrobiens est une menace sérieuse en médecine humaine et vétérinaire. Parmi les organismes résistants les plus problématiques figurent les entérobactéries productrices de bêtalactamases à spectre étendu (ESBL), qui sont résistantes aux céphalosporines de 3e génération. Le but de cette étude était de déterminer la fréquence de colonisation des chevaux admis au Western College of Veterinary Medicine par des Escherichia coli résistants. Unassigned: Des écouvillons rectaux ont été effectués sur 60 chevaux admis entre novembre 2021 et mars 2022. Les écouvillons ont été cultivés de manière sélective pour E. coli, qui a été identifié à l’aide de tests biochimiques standards. La sensibilité aux antimicrobiens des isolats a été déterminée et les isolats résistants ont été examinés par PCR pour la présence d’ESBL. Unassigned: Escherichia coli a été isolé chez les 60 chevaux. Bien que la pansensibilité était le phénotype le plus fréquemment identifié, des isolats multirésistants possédant une ESBL de type CTX-M ont été retrouvés chez 1 cheval. La résistance au triméthoprime-sulfaméthoxazole était le phénotype de résistance le plus fréquemment rencontré. Unassigned: Bien que la résistance fût rare, l’identification d’isolats producteurs d’ESBL a souligné l’importance d’une surveillance continue pour détecter l’émergence de la résistance dans les populations équines.(Traduit par Dr Serge Messier).
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This research conducted a study to determine the frequency of colonization of horses with antimicrobial resistant Escherichia coli at the Western College of Veterinary Medicine. Though the presence of resistance was uncommon, this study highlights the importance of ongoing surveillance for the emergence of resistance in equine populations.
Method of Research
The study took rectal swabs from 60 horses admitted to the Western College of Veterinary Medicine between November 2021 and March 2022.
The swabs were selectively cultured for Escherichia coli.
The bacteria were identified using standard biochemical tests.
The researchers determined the antimicrobial susceptibility of the isolates.
They screened the resistant isolates with PCR for the presence of extended-spectrum β-lactamase (ESBL).
Results of the Study
Escherichia coli was isolated from all 60 horses involved in the study.
Though the most common phenotype identified was pansusceptibility, multidrug-resistant isolates possessing a CTX-M-type ESBL were found in one horse.
The most frequently encountered resistant phenotype was resistance to trimethoprim + sulfamethoxazole.
Implications of the Study
The identification of ESBL-producing isolates, though uncommon, emphasised the importance of continued surveillance to monitor the emergence of resistance in equine populations.
This study proves that antimicrobial resistance is a serious challenge in veterinary medicine, especially regarding resistance organisms like ESBL-producing Enterobacterales, which are resistant to the 3rd-generation cephalosporins.
Cite This Article
APA
Polo MC, Huby FD, Uehlinger FD, Rubin JE.
(2025).
Survey of the antimicrobial susceptibility of Escherichia coli isolated from horses admitted to the Western College of Veterinary Medicine, Saskatoon, Saskatchewan.
Can Vet J, 66(4), 435-439.
Department of Large Animal Clinical Sciences (Polo, Uehlinger) and Department of Veterinary Microbiology (Huby, Rubin), Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4.
Huby, Florence D
Department of Large Animal Clinical Sciences (Polo, Uehlinger) and Department of Veterinary Microbiology (Huby, Rubin), Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4.
Uehlinger, Fabienne D
Department of Large Animal Clinical Sciences (Polo, Uehlinger) and Department of Veterinary Microbiology (Huby, Rubin), Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4.
Rubin, Joseph E
Department of Large Animal Clinical Sciences (Polo, Uehlinger) and Department of Veterinary Microbiology (Huby, Rubin), Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4.
MeSH Terms
Animals
Horses
Escherichia coli / drug effects
Escherichia coli / isolation & purification
Saskatchewan / epidemiology
Anti-Bacterial Agents / pharmacology
Escherichia coli Infections / veterinary
Escherichia coli Infections / microbiology
Escherichia coli Infections / epidemiology
Horse Diseases / microbiology
Horse Diseases / epidemiology
Microbial Sensitivity Tests / veterinary
Drug Resistance, Multiple, Bacterial
beta-Lactamases
Drug Resistance, Bacterial
Male
Female
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