Prevalence of antimicrobial resistance and resistance genes in faecal Escherichia coli isolates recovered from healthy pets

Abstract

Faecal samples of healthy dogs (n=39) and cats (n=36) obtained in Northern Portugal were seeded on Levine agar plates, and two Escherichia coli isolates per sample were recovered (78 of dogs and 66 of cats). The susceptibility to 16 antimicrobial agents was tested in this series of 144 E. coli isolates. Almost 20% of them showed tetracycline resistance and 12 and 15% presented ampicillin or streptomycin resistance, respectively. The percentage of resistance to the other antimicrobial agents was in all cases below 4%, and no resistant isolates were detected for ceftazidime, imipenem, cefoxitin or amikacin. Two isolates (from one dog) showed cefotaxime-resistance and harboured both the CTX-M-1 and OXA-30 beta-lactamases. A bla(TEM) gene was detected in 12 of 17 ampicillin-resistant isolates, the aac(3)-II gene in the three gentamicin-resistant isolates, aadA in 7 of 22 streptomycin-resistant isolates, and tet(A) and/or tet(B) gene in all 28 tetracycline-resistant isolates. The gene encoding class 1 integrase was detected in six E. coli isolates, including the four trimethoprim-sulfamethoxazole-resistant isolates and those two harbouring CTX-M-1 and OXA-30 beta-lactamases; different gene cassette arrangements were identified: dfrA1+aadA1 (two isolates), dfrA12+orfF+aadA2 (two isolates) and bla(OXA30)+aadA1 (two isolates). One amino acid change in GyrA protein (Ser83Leu or Asp87Tyr) was detected in four nalidixic acid-resistant and ciprofloxacin-susceptible isolates and two amino acid changes in GyrA (Ser83Leu+Asp87Asn) and one in ParC (Ser80Ile) were identified in one nalidixic acid- and ciprofloxacin-resistant isolate. Faecal E. coli isolates of healthy pets could be a reservoir of antimicrobial resistance genes.

Detection of virulence and antimicrobial resistance genes in Escherichia coli isolates from diarrhoiec dogs in Iran

“…E. coli develop resistance following prolonged exposure to antibacterial agents especially in sub-therapeutic doses by acquisition of antibacterial resistance genes from other resident commensal or transient pathogens colonising the individual or the environment. Various antimicrobial resistance determinants including multidrug resistance genes encoding for extended-spectrum β-lactamases have been described in E. coli isolates from companion animals (Bradford 2001, Costa et al 2008, Ewers et al 2010, Shaheen et al 2011, Tajbakhsh et al 2015. Antimicrobial resistance genes spread easily among bacterial organisms by mobile genetic elements like plasmids, and transposons (Salvadoris et al 2003, Randall et al 2004.…”

“…Isolation of diarrhoeagenic antimicrobial-resistant E. coli from dogs with or without diarrhoea and/or their handlers have been reported in countries such as Italy (Carattoli et al 2005), Portugal (Costa et al 2008, Bien et al 2011, Poland (Rzewuska et al 2015), Brazil (de Almeida et al 2012, Paula and Marin 2008, Paula and Marin 2009, Siqueira et al 2009, Puno-Sarmiento et al 2013, the Netherlands (Ewers et al 2010, Ewers et al 2012, Argentina (Bentancor et al 2007), America (Shaheen et al 2011), and Egypt (Ali andMetwaly 2015, Yunis et al 2015). In the available literature, studies on pathogenic E. coli in diarrhoeic and/or healthy dogs in Iran include the reports of Zahrei Salehi et al (2011) and Koochakzadeh et al (2014).…”

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“…For the veterinarian, knowing the bacterial species possibly involved in the most frequently encountered infectious conditions and their possible resistance to antimicrobials is important. Various longitudinal retrospective studies in Europe [5,6] and North America [7,8] have reported an increase in the prevalence of antimicrobial resistance among the commensal E. coli strains isolated from pets. All of them reported a resistance percentage of E. coli isolates from healthy cats quite similar to those reported in the present study, especially Costa et al [5].…”

“…Various longitudinal retrospective studies in Europe [5,6] and North America [7,8] have reported an increase in the prevalence of antimicrobial resistance among the commensal E. coli strains isolated from pets. All of them reported a resistance percentage of E. coli isolates from healthy cats quite similar to those reported in the present study, especially Costa et al [5]. However some exceptions could be found among the quinolones (nalidixic acid) and fluoroquinolones (ciprofloxacin) with percentages of 24.7% and 10.1% respectively reported by Leite-Martins et al [6], and also among the cephalosporin (3th generation) ceftazidime 10.1% [6].…”

“…Only a few authors have reported the antimicrobial resistance in commensal E coli isolates recovered from cats and most of them are from Europe [5,6] and Canada [7,8], nevertheless, to our knowledge, there is no previous study carried out with cats in Brazil. The aim of the present study is to verify the antimicrobial resistance detected among E. coli isolates from diarrheic or healthy cats.…”