ANTIBIOTIC RESISTANCE AND ZOONOTIC POTENTIAL OF ESCHERICHIA COLI STRAINS ISOLATED FROM POULTRY AGRO-INDUSTRIAL COMPLEX

Poultry is a source of antibiotic--resistant and potentially pathogenic Escherichia coli, which can circulate in enterprises and enter the environment through organic waste. The aim of the study was to analyze antimicrobial resistance profiles, pathogenicity genes and phylogroups of E. coli strains circulating in poultry farms in the Perm Region. The strains of three different groups were studied: those isolated from healthy birds (n=16), chickens with colibacteriosis (n=28) and organic waste (n=19). PCR was used to detect antibiotic resistance and virulence--associated genes. In each of the groups, multidrug--resistant E. coli were found in 18.8 %, 75 % and 73.7 % of cases, respectively. Up to 6 antibiotic resistance genes were detected in E. coli genomes. The beta-lactamase blaTEM gene was found most often in all groups. More than half of the E. coli obtained from sick chickens carried blaCTX-M. A high proportion of E. coli encoding SHV type beta-lactamase (63.2 %) was found in the organic waste. Among them, the tetA efflux system gene was detected more often, and in this group more than 20 % of E. coli had the genes encoding QnrB and QnrS proteins responsible for plasmid--mediated resistance to fluoroquinolones. Most of the strains obtained from healthy birds belonged to phylogroup E, from sick birds - to B1, isolated from organic waste - to C or E.Avian pathogenic E. coli (APEC), including high-risk clones, were found with high frequency in the group of sick birds (75 %), were found in the group of healthy birds (6.3 %) and were preserved in organic waste (63.2 %). Most of the analyzed E. coli (54 %) carried combinations of marker genes both extraintestinal and intestinal E. coli, which indicates their high zoonotic potential.