Investigation and characterization of Aliarcobacter spp. isolated from cattle slaughterhouse in Türkiye

Abstract Aliarcobacter spp. have has been isolated from numerous food products at retail and from animal carcasses and feces at slaughter. The objectives of this study were: i) to isolate Aliarcobacter species (Aliarcobacter butzleri, Aliarcobacter skirrowii, Aliarcobacter cryaerophilus) from different slaughterhouses’ samples, ii) to detect genetic diversity, antibiotic resistance, biofilm ability and putative virulence gene profiles of the isolates. The antibiotic susceptibility to antimicrobials was examined using the Kirby-Bauer disc diffusion method. A molecular investigation of antibiotic resistance and virulence factors was also conducted using polymerase chain reaction (PCR). A total of 22 (14.6%) Aliarcobacter spp. isolates were obtained, with varying levels of antibiotic resistance observed. The genes tetO, tetW, and gyrA were detected in 0%, 31.8%, and 27.2% of the isolates, respectively. All isolates were resistant to ampicillin, rifampin, and erythromycin, while tetracycline was found to be the most effective antibiotic, with 81.8% of the isolates showing susceptibility to it. In terms of virulence factors, all isolates (100%) harbored more than one of the nine putative virulence genes tested, with 18.1% of isolates carrying more than three. Regarding biofilm formation, 7 (31.8%) and 4 (18.1%) isolates were found to form strong and moderate biofilms, respectively, while one (4.5%) isolate was classified as a weak biofilm producer. ERIC-PCR band patterns suggested that the isolated Aliarcobacter spp. from slaughterhouses had different sources of contamination. These findings highlight the potential risk posed by pathogenic and multidrug-resistant Aliarcobacter spp. in food, and the need for control measures throughout the food chain to prevent the spread of these strains. The results indicate that foods of animal origin and cattle slaughterhouses are significant sources of antimicrobial resistant Aliarcobacters.