The promising activity of apple cider vinegar on MDR Klebsiella spp. (K. variicola and K. pneumoniae) emerging pathogens in chicken.

Klebsiella spp. is identified as a zoonotic pathogen with a growing concern for poultry. To address this pathogen, 125 chicken samples were collected. Klebsiella variicola (K. variicola) was first detected in Egypt. The findings revealed an isolation of (30.4%) of Klebsiella spp (K. pneumoniae (94.7%) and Klebsiella variicola (K.variicola) (5.3%). The capsular typing of K. pneumoniae isolates revealed that 15.8%, 36.8%, 10.5%, 26.3%, and 5.3% belonged to phylogenetic groups K1, K2, K5, K54, and K57, respectively. The Klebsiella isolates exhibited remarkable resistance against ampicillin (94.7%), cefotaxime (89.5%), and ceftazidime (86.9%). Notably, 91.6% of the isolates were susceptible to imipenem, making it a drug of choice. 50% of Klebsiella isolates were XDR, while 47.4% were MDR with MAR indices ≥ 0.5, indicating they originated from high-risk contamination sources. 97.4% of isolates harbored at least one β-lactams resistance gene, of which blaTEM (92.1%), blaSHV (89.5%), blaCTXM-1 (84.2%), and blaDHA (50%). 7.9% of the investigated isolates possessed all carbapenemase genes (blaNDM-1, blaIMP-1, blaKPC). Considering non-ESBLs, 84.2% of isolates harbored the tetA gene, while 63.2%, 52.6%, and 50% were positive for sul1, aadA, and qnrA genes. ureA, mrkD, entB genes were the most prevalent ones (100%), followed by fimH, mrkA, uge (94.7%), iutA (84.2%), iroN (73.9%), rmpA (39.5%), and magA (13.2%), with no detection of clbA and clbB genes. Our strains are genetically identical to human isolates. Our data indicated multiple health risks linked to phenotypic and genotypic resistance, as well as zoonotic importance. The Apple Cider Vinegar (ACV) possesses significant antibacterial properties.