# Antimicrobial Resistance in Escherichia coli from Captive Wild Felids: Associations with Host and Management Factors

## TL;DR

This study examines antibiotic-resistant Escherichia coli in captive wild cats and finds that certain captive conditions are linked to resistance, highlighting risks to human and animal health.

## Contribution

The study identifies associations between captive management factors and antimicrobial resistance in wild felid E. coli, emphasizing the need for AMR surveillance in captivity.

## Key findings

- E. coli isolates showed resistance to tetracycline and ampicillin, with some being multidrug-resistant.
- Biofilm formation was the only virulence factor detected among the isolates.
- Human proximity and enclosure type were significantly associated with resistance outcomes.

## Abstract

Antimicrobial resistance enables microorganisms to survive established treatments protocols and represents a growing problem that affects both human and animal health. In this study, we investigated the antimicrobial resistance profiles of Escherichia coli isolated from captive wild felids. Our aim was to assess whether captive conditions influence the presence of resistant bacteria and whether these bacteria may pose a risk to human health. Faecal samples were collected from several captive animals, from which E. coli isolates were obtained and analysed for their resistance and virulence profiles. The results showed that some isolates were resistant to multiple antibiotics, and that certain captive conditions appeared to be associated with the presence of resistant isolates. These findings highlight the importance of monitoring bacteria in captive wildlife, not only to protect animal health but also to reduce the potential risk of transmission of resistant strains to humans. Identifying resistant bacteria and associated circumstances may help guide strategies to limit the spread of antimicrobial resistance, contributing to both public health and animal welfare.

Understanding antimicrobial resistance (AMR) within a One Health framework requires examining how human–animal–environment interactions shape bacterial populations, and captive wildlife offers a unique context to explore these dynamics. This study aimed to characterise the phenotypic resistance and virulence profiles of Escherichia coli isolated from faecal samples of captive non-domestic felids housed in a wildlife sanctuary in the United Kingdom and evaluate the influence of captive conditions in E. coli traits. A total of 41 faecal samples were collected from 36 animals representing 11 non-domestic felid species, from which it was possible to obtain 108 E. coli isolates identified using IMViC testing. The isolates were characterised regarding their susceptibility to 12 antibiotics by disc diffusion and screened for the phenotypic expression of six virulence factors, including protease, DNase, gelatinase, lecithinase, haemolysins, and biofilm formation. The highest resistance rates were observed for tetracycline (19.4%) and ampicillin (10.2%), while isolates presented complete susceptibility regarding half of the tested antibiotics. Also, 9.3% of the isolates presented a multidrug-resistant profile. Biofilm formation was the only virulence factor expressed by the isolates under study (8.3%). Significant associations were detected between resistance outcomes and levels of human proximity and enclosure type. These findings suggest that captivity-related factors may influence AMR profiles in wild felids and highlight the importance of continued AMR surveillance and appropriate management practices to reduce selective pressures in captive wildlife.