Antimicrobial Resistance and Multidrug-Resistant Escherichia coli in Apparently Healthy Dogs in Rayfield, Jos, Nigeria

Abstract

Brief Background/Aim: Growing concerns regarding antimicrobial-resistant (AMR) Escherichia coli in companion animals, with special reference to dogs, from a One Health perspective is vital due to their close contact with humans and potential role in silent zoonosis and AMR transmission. However, most existing studies focus on clinically ill dogs, leaving gaps in understanding carriage among apparently healthy animals. This study described the occurrence of AMR Escherichia coli in apparently healthy dogs. Study Design: Cross-sectional study. Place and Duration of Study: This study was conducted in the Diagnostic Laboratory of National Veterinary Research Institute, Vom. Samples were obtained from dogs in Rayfield, Jos, Nigeria in the period from July 2024 to August 2024. Methodology: Rectal swabs were collected from 100 apparently healthy dogs (50 each per breed) and cultured for Escherichia coli (E. coli) isolation and confirmation. Antimicrobial susceptibility testing was performed on the E. coli isolates (n=13) using 10 antibiotics selected based on regional resistance pattern. This testing was done in accordance with the Clinical and Laboratory Standards Institute guidelines. Descriptive analysis was conducted using STATA 17 and results for frequencies and proportions were presented in tables and charts. Results: From the equal number of exotic and mongrel dog breeds, most were demographically between 4 and 6 years old (46/100) and female (54/100). The overall prevalence of Escherichia coli was 13% (13/100). Most isolates occurred among dogs aged 4–6 years (53.9%), females (69.2%), and mongrel breeds (53.9%). The bacteria showed greatest resistance to amoxicillin (76.9%, 10/13), followed by ciprofloxacin (69.23%, 9/13) and sparfloxacin (53.85%, 7/13). In contrast, the highest susceptibility was observed to ofloxacin (69.2%) followed by gentamicin (61.5%). Multidrug resistance was detected in 69% (9/13) of isolates. Conclusion: This study demonstrates the presence of multidrug-resistant E. coli in apparently healthy domestic dogs, indicating their potential role as silent reservoirs of AMR. The high resistance to commonly used antibiotics highlights the need for strengthened antimicrobial stewardship in veterinary practice. These findings stress the importance of routine surveillance and One Health–oriented strategies to limit interspecies transmission and protect both animal and public health.