The increasing prevalence of antibiotic-resistant bacteria, especially Klebsiella spp., represents a major threat to both human and veterinary medicine. This study aimed to isolate and characterize the antimicrobial resistance profiles of Klebsiella spp. from broilers and broiler bursitis.
A total of 210 samples were collected, including 70 from hens, 40 from free-range chickens, 40 from bursitis, 20 from males, 20 from roosters, and 20 from young chickens. Antimicrobial susceptibility testing was conducted using the disc diffusion method, as recommended by EUCAST and CLSI guidelines, against 14 antibiotics. Additionally, PCR analysis revealed the presence of several resistance genes.
From the 210 samples, 51 isolates of Klebsiella spp. were obtained, including 20 from hens, 10 from young chickens, 8 from bursitis, 6 from free-range chickens, 4 from roosters, and 3 from males. Regarding the antimicrobial resistance, 57% of the isolates were classified as multidrug-resistant. The highest levels of resistance were observed for ampicillin (98.04%) and amoxicillin-clavulanic acid (86.27%). Resistance to nalidixic acid, trimethoprim-sulfamethoxazole, ciprofloxacin, gentamicin, and tetracycline was detected in 52.94%, 50.98%, 47.06%, 45.10%, and 23.53% of the isolates, respectively. None of the isolates showed resistance to imipenem, cefotaxime, or ceftazidime. The sul2 gene was detected in 65.39% of isolates resistant to trimethoprim-sulfamethoxazole, while sul3 was found in only 3.85%. The blaTEM gene, associated with beta-lactam resistance, was present in 78% of isolates, while blaSHV was detected in 4%. For tetracycline resistance, the tetA and tetB genes were found in 58.33% and 41.67% of the isolates, respectively.
This study highlights the significant antimicrobial resistance found in Klebsiella spp. isolated from poultry, underscoring the public health risks associated with the consumption of poultry products. More than half of the isolates were multidrug-resistant, which calls for ongoing surveillance and responsible antibiotic use in animal production to mitigate the spread of resistant strains.
