Virulence properties and antimicrobial susceptibility profiles of Klebsiella species recovered from clinically diseased broiler chicken

Abstract

E. coli, Klebsiella species are normal intestinal flora of poultry, but could cause infections whenever the immune system of affected bird is compromised. This study was conducted to determine the occurrence of Klebsiella species in clinically diseased chickens with determination of its virulence properties and their antibiotic resistance profile. 200 tissue samples collected from 50 clinically diseased chicken organs (lungs, liver, spleen, and heart) four samples per each bird were screened for the presence of Klebsiella spp. by standard bacteriological methods. Klebsiella spp. isolates were screened for the presence of selected virulence genes including, rmpA (regulator of the mucoid phenotype A), magA (mucoviscosity associated gene) and haemolysin. In addition, Klebsiella spp. isolates were studied for their susceptibility patterns to various antibiotics by disc diffusion method. 30 (15%) isolates were identified as Klebsiella spp. differentiated into 73.33 % (22/30) K. pneumoniae and 26.67 % (8/30) K. oxytoca. Klebsiella isolates were confirmed by PCR using gyrA gene. The rmpA identified in 46.67% (14/30), magA was identified in 53.33% (16/30) isolates, meanwhile, hemolytic activity was detected in 40% (12/30). Klebsiella isolates showed a high resistance to amoxacillin (AX, 100%), amoxicillin /clavulanic acid (100%), piperacillin (86.67%), cefotaxim (86.67%), aztreonam (83.33%), cefapime (70%), ceftriaxone (66.67%) and ciprofloxacin (66.67%), a moderate resistant to chloramphenicol (46.67%), neomycin (33.3%) and norofloxacin (30%). On the other hand, Klebsiella isolates showed the lowest resistance to amikacin (10%). In conclusion, distribution of virulence profile indicates the role of rmpA and magA in pathogenicity of Klebsiella spp. in respiratory infections. Antimicrobial susceptibility pattern showed high multiple antibiotic resistances which require strict regulations antibiotics uses in veterinary therapy.