Serotyping, RAPD PCR, Antibiotic Susceptibility Profiling of Listeria spp. Isolated from Raw Chicken Meat

Abstract

The present study was aimed at finding the prevalence, serotyping, RAPD and Setyping of Listeria monocytogenes in raw chicken meat purchased from different retail outlets and local butcher shops across the Nagpur city. Cultural examination of 100 raw poultry meat samples, revealed the prevalence of Listeria spp. (35 %). L. grayi was predominant (15 %) among the isolates followed by L. monocytogenes (12 %), L. welshimeri (5 %), L. innocua (2 %) and L. seeligeri (1%) respectively. Among the majority of strains of L. monocytogenes, virulence marker genes hlyA and iap, all together or in combination were detected. Serotyping PCR study revealed that all L. monocytogenes isolates to be serotype 4b, which is the major serotype involved in the human listeriosis. RAPD PCR analysis of L. monocytogenes isolates revealed two types of banding patterns. All 35 strains of Listeria showed in-vitro susceptibility to antibiotics like vancomycin (93.88 %) ceftriaxone + Tazobactum (92.71%) and moderate sensitivity to enrofloxacin (38.78 %), ceftriaxone (34.90%) and ampicillin (34.69 %). Whereas, all the isolates were least sensitive to erythromycine (6.49%) and sulphasomidine (4.08 %). All the Listeriae isolates were refractory to penicillin. The present findings indicate the presence of multiple drug resistance among L. monocytogenes and other Listeria spp. isolated from raw poultry meat samples. Potentially pathogenic L. monocytogenes isolates recovered from raw poultry meat samples also signifies the zoonotic potential of listeriosis in the local area of Nagpur. High prevalence of L. monocytogenes and other Listeria spp. in raw poultry meat and their sensitivity to the antibiotics tested, clearly indicates that vancomycin and ceftriaxone +tazobactam should be used as a drug of choice for treatment of listeriosis. Keywords: Serotyping PCR, RAPD, Antibiotic Sensitivity test, ceftriaxone, sulphasomidine, tazobactam