Molecular detection of Shiga toxin and extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli isolates from sheep and goats

Abstract

Background The Shiga toxin (Stx)-producing Escherichia coli (STEC) have become important global public health concerns. This study investigated the prevalence, antimicrobial resistance profile, and extended-spectrum beta-lactamase-producing E. coli in sheep and goat faeces. Methods and results A total of 53 E. coli isolates were confirmed by PCR targeting the uidA [β-D glucuronidase] gene. The Shiga toxin genes stx1 and stx2, as well as bfpA, vir, eaeA, lt and aafII virulence genes, were detected in this study. Of the 53 isolates confirmed to be STEC, 100% were positive for stx2 and 47.2% for stx1. Three isolates possessed a combination of stx1 + stx2 + eaeA, while four isolates harboured stx1 + stx2 + vir virulence genes. The isolates displayed phenotypic antimicrobial resistance against erythromycin (66.04%), colistin sulphate (43.4%), chloramphenicol (9.4%) and ciprofloxacin (1.9%). A total of 28.8% of the strains were phenotypically considered ESBL producers and contained the beta-lactamase blaCTX-M-9 and blaCTX-M-25 gene groups. A larger proportion of the E. coli strains (86.8%) contained the antibiotic sulphonamide resistant (sulII) gene, while 62.3%, 62.3%, 52.8%, 43.4%, 41.5%, 20.8%, 18.9%, 11.3%, 11.3%, 9.4%, 9.4% and 5.7% possessed mcr-4, floR, mcr-1, tet(A), sulI, tet(O), tet(W), parC, mcr-2, ampC 5, qnrS and ermB genes, respectively. Thirteen isolates of the ESBL-producing E. coli were considered multi-drug resistant (MDR). One Shiga toxin (stx2) and two beta-lactamase genes (blaCTX-M-9 and blaCTX-M-25 groups) were present in 16 isolates. In conclusion, the E. coli isolates from the small stock in this study contained a large array of high antibiotic resistance and virulence profiles. Conclusions Our findings highlight the importance of sheep and goats as sources of virulence genes and MDR E. coli. From a public health and veterinary medicine perspective, the characterization of ESBL producers originating from small livestock (sheep and goats) is crucial due to their close contact with humans.

Detection of Salmonella Pathogenicity Islands and Antimicrobial-Resistant Genes in Salmonella enterica Serovars Enteritidis and Typhimurium Isolated from Broiler Chickens

“…Primarily, antimicrobial drugs are essential to both human and animal health and survival on a global scale [17]. In the Alborz Province of Iran, Sodagari et al [47] first introduced tetracycline as the most efficient antibiotic against Salmonella in chickens.…”

“…The global rise of antibiotic resistant (AR) bacteria is a major public health problem [1]. Antibiotic resistance genes (ARGs) have emerged in human and animal infections due to the excessive use of antimicrobial drugs in animals raised for food, frequently without the advice or supervision of a specialist [16,17]. The first report of Salmonella resistance to a single antibiotic was published in the early 1960s [18].…”

Exploring Extended-Spectrum Beta-Lactamase (ESBL)-Producing Escherichia coli in Food-Producing Animals and Animal-Derived Foods

“…A study examining ESBL-producing E. coli in sheep and goats revealed antimicrobial resistance patterns in both healthy and diarrheic animals [ 26 ]. Furthermore, there are reports of some strains potentially capable of producing Shiga toxin and carrying genes associated with ESBL production in these animals [ 27 ].…”