Assessment of antimicrobial resistance patterns in kennel-associated Enterobacterales isolates from canine patients and evaluation of alternative therapeutic strategies.

Project Abstract

The rising prevalence of antimicrobial resistance (AMR) among Enterobacterales isolated from canine clinical samples in kennel settings presents significant challenges for veterinary therapeutics and public health, necessitating a comprehensive assessment of resistance patterns and the exploration of viable alternative therapies. This study undertakes a cross-sectional surveillance of Enterobacterales isolates collected from kennel-associated canine patients across multiple diagnostic laboratories over a 24-month period, aiming to characterize antimicrobial susceptibility profiles, identify prevalent resistance determinants, and evaluate the potential utility of non-traditional and adjunctive therapeutic strategies. Phenotypic antimicrobial susceptibility testing was performed using standardized broth microdilution methods in accordance with CLSI guidelines; molecular analyses including PCR and whole-genome sequencing were employed to detect resistance genes (e.g., blaCTX-M, blaTEM, blaSHV, blaOXA-48-like, and qnr variants) and to elucidate clonal relationships via multilocus sequence typing and core-genome SNP analysis. Data were stratified by kennel type (breeding, boarding, and rescue facilities), age, sex, prior antibiotic exposure, and comorbidities to identify risk factors associated with multidrug-resistant (MDR) phenotypes. The prevalence of ESBL-producing Enterobacterales and AmpC producers was quantified, and the distribution of resistance determinants across species (Escherichia coli, Klebsiella spp., Enterobacter spp.) was delineated. In addition to conventional antibiotics, the study evaluated the in vitro efficacy of alternative therapeutic options, including phage therapy candidates, antimicrobial peptides, bacteriophage-derived lytic enzymes, and bactericidal anaerobic conditions, as well as combination regimens with approved non-antibiotic adjuvants (e.g., efflux pump inhibitors, anti-biofilm agents). In vitro synergy testing and time-kill assays were conducted to identify promising combinations, followed by preliminary in vivo feasibility assessments in a subset of clinically affected dogs under owner consent, focusing on safety, tolerability, and pharmacokinetic considerations. The results revealed a high burden of MDR phenotypes with notable associations to prior antibiotic exposure and kennel management practices, including frequent use of third-generation cephalosporins and fluoroquinolones. Molecular analyses uncovered a diverse resistance gene repertoire with clonal clusters suggesting both local clonal expansion and inter-facility transmission. Alternative therapeutic strategies demonstrated several synergistic interactions in vitro, with phage-based approaches and certain antimicrobial peptides showing potential against ESBL and AmpC producers, while non-antibiotic adjuvants enhanced the activity of conventional agents in resistant isolates. However, translation to in vivo efficacy required careful assessment of host safety and ecological impact on the canine gut microbiome. The study highlights the urgency of implementing stewardship programs within kennels, including rapid diagnostic workflows, targeted antibiotic selection guided by local antibiograms, vaccination and infection control measures, and prudent use of last-resort antimicrobials. It also provides a framework for integrating innovative therapeutics into veterinary practice, emphasizing translational research pathways, regulatory considerations, and collaborative efforts among clinicians, microbiologists, and animal welfare organizations. The findings underscore the potential of combining surveillance data with targeted non-traditional therapies to mitigate AMR threats in companion animal populations while safeguarding public health.

Project Overview

What This Project Is About

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A plain-language overview of the topic and what the project investigates.

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The Problem It Addresses

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What problem or gap this project tackles and why it matters to the field or society.

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Objectives of the Project

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1. Identify common bacteria in kennel dogs that belong to the Enterobacterales group.
2. Test these bacteria to see which antibiotics they resist and which still work.
3. Explore alternative treatment ideas when standard antibiotics fail.

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What You Will Do Step by Step

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1. Collect bacterial samples from dogs treated at veterinary clinics or kennels.
2. Identify the bacteria and confirm they are Enterobacterales.
3. Perform simple antibiotic tests to check resistance patterns.
4. Review current treatment options and note any failures or limitations.
5. Look into alternative therapies or strategies that could help when resistance occurs.
6. Summarize findings and consider practical implications for vets.

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Expected Outcome

Expect a clear map of which antibiotics are less effective against kennel-associated Enterobacterales and practical, evidence-based ideas for alternative treatments that could be used in dogs.