Profiles of antimicrobial resistance of enterobacteria isolated at livestock enterprises of the Ural region

Abstract

Abstract. A study of the antibiotic susceptibility of bacteria of the genus Enterobacter, selected at regional dairy enterprises, was carried out. The purpose of this work was to assess the phenotypic resistance profiles of Enterobacter spp. in the loci of fermenal microbiocenoses related to milk production. Research methodology and methods. In the course of the work carried out, milk, mammary gland secretions, and udder washes from cows at dairy cattle breeding enterprises located in different districts of the Ural region were examined. The phenotypic resistance of Enterobacter spp. Isolates was analyzed to 10 antibacterial drugs: ciprofloxacin, enrofloxacin, ofloxacin, meropenem, doxycycline, chloramphenicol, ceftriaxone, amoxicillin, ampicillin, rifampicin. Results. Average sensitivity values of Enterobacter spp. for all surveyed enterprises were at the level of 2.0–3.3 conventional units (at maximum = 4) to target antibiotics, and at the level of 2.0–2.1 conventional units to non-target antibiotics. The highest bactericidal efficacy was found in fluoroquinolones, the lowest in doxycycline and chloramphenicol. For individual enterprises, the average resistance profile included good sensitivity to 3–4 antibiotics, reduced to 4–5 and resistance to 1–2 antibiotics. The main conclusion is that in eight surveyed enterprises, the usual pattern was the resistance of isolates or their low sensitivity to several antibiotics of different classes, which indicates an unfavorable situation with AMR. Scientific novelty. The results obtained in the course of the work performed made it possible to assess the current and actual levels of resistance of Enterobacter spp. Isolates inhabiting those loci of fermenal microbiocenoses that are directly related to milk production.