Occurrence of escherichia coli as a causative agent of enteritis in dogs with special reference to their multidrug resistance and virulence genes

Abstract

Escherichia coli (E. coli) massively causes deaths all around the world. Human–pet proximity may inadver-tently harm humans. Dogs are susceptible to virulent E. coli strains causing enteric infections in humans. In the present study, a total of 90 rectal swabs were collected from dogs of different ages (suffered from diarrhea with fever, nausea, chills, loss of appetite, and bloating) at different veterinary hospitals and clinics in Cairo to determine the incidence rate of E. coli and their virulence and resistance genes. Bacteriological examination revealed an overall E. coli occurrence rate of 67.7% (61/90). The highest isolation rate of 75.5% was from puppies that were 3 months and more. Serotyping of ten E. coli isolates showed that they belonged to seven serogroups O18, O27, O55, O126, O148, O158, and O166 and other untypable three strains. All E. coli isolates were subjected to disc diffusion sensitivity tests and were resistant to tetracycline, trimethoprim/ sulphamethoxazole (100% for each), cefotaxime (95.1%), and erythromycin (93.4%), while they were sensitive to amikacin only (88.5%). The occurrence of virulence genes in the seven tested E. coli isolates was conducted using PCR. It was revealed that the stx1 gene was detected in O18, O126, O148, O158, and O166 se-rogroups while the stx2 gene was detected in O18 and O27 only. The eaeA gene was detected in O27, O55, O148, and O158 serogroups. Also, the antibiotic-resistant blaTEM and tetA genes were detected in all the seven tested serotypes. These combined results indicate that pet animals may harbor E. coli causing diarrhea at different ages.