Isolation and Identification of Salmonella spp. from Broiler Chicken Meat in Sri Lanka and their Antibiotic Resistance

Abstract

Purpose : Salmonella infections continue to be a global problem with millions of humans and animal cases occurring annually. Broiler chicken plays a significant role causing Salmonella infections in Sri Lanka. Consumption of food contaminated with antimicrobial resistant Salmonella aggravates the problem. This study isolated, identified, and serotype the Salmonella spp. from broiler chicken meat in Sri Lanka and examined their antimicrobial susceptibility to be used in establishment of control measures. Research Method : Isolation of Salmonella species from broiler chicken meat was done by conventional method of isolation followed by polymerase chain reaction (PCR) confirmation. All PCR confirmed isolates of Salmonella were serotype and then, isolates were tested for antibiotic susceptibility using disc diffusion assay followed by the detection of antibiotic resistance genes using PCR. Findings : Broiler chicken meat in Sri Lanka is contaminated with Salmonella spp. at the prevalence of 11.6% and 8.9% of them carried hns and invA specific genes. Isolates were serotyped as Salmonella Typhimurium (47.8%), Salmonella Enteritidis (26.1%) and non typable (26.1%). Three isolates were resistant to ampicillin. Intermediate resistance was shown to three antibiotics and all the isolates were sensitive to nine antibiotics. Majority (56.5%) of Salmonella were sensitive to all the tested antibiotics. Prevalence of resistant genes for tetracycline, sulfonamides and aminoglycosides were within 4%-26%. None of the isolates except one (4%) carried chloramphenicol resistance genes. Originality / Value : Steps must be taken to minimize contamination of broiler chicken meat with Salmonella spp in Sri Lanka. Although, there is a low prevalence of antibiotic resistant isolates, its mere presence in broiler chicken is a warning signal of possibility of emergence of multidrug resistant strains