Abstract
Background: Poultry is considered as a major source of human contamination with nontyphoidal Salmonella species. Global concern regarding the emergence and dispersion of
extended-spectrum beta-lactamase (ESBLs)-producing isolates in broilers has increased during
recent years.
Objective: This study was proposed to evaluate the prevalence of Salmonella and the associated
ESBLs in broilers in Lorestan province of Iran.
Materials and Methods: Five hundred fresh fecal samples of broilers were phenotypically screened
for Salmonella. The isolates were confirmed molecularly using an invA-based polymerase chain
reaction (PCR). Confirmatory combination disk method was applied for phenotypic detection
of ESBLs among the isolates, followed by molecular identification of blaCTX-M, blaTEM, and blaSHV
genes in 3 single PCR assays among positive isolates. Chi-square test in SPSS software was used
for the assessment of statistical relationships.
Results: Of the 95 Salmonella isolates detected using routine bacteriological methods, all were
confirmed molecularly. They generated the expected 254-bp amplicon. Moreover, 13 isolates
were phenotypically recognized as ESBL determinants, among which 9 and 4 harbored blaCTX-M
and blaTEM, respectively. No blaSHV and co-existence of the genes were determined.
Conclusion: The threat imposed by dissemination of ESBL-producing non-typhoidal Salmonella
spp. isolated from broilers was confirmed in the studied region. Continuous monitoring programs,
application of biosecurity measures, and prudent prescription of antibiotics are warranted in
order to prevent the introduction or dispersion of the ESBL-producing Salmonella.