Molecular identification of beta-lactamase-producing Salmonella enteritidis from broiler chickens

Abstract EN

The present study was aimed to investigate the prevalence of multidrug resistant S.

enteritidis in broiler chicken flocks (n=15)suffering from diarrhea during the period of 2015 in El-Beheira governorate.

A total of 210 tissue swabs (liver, intestine, spleen and gall bladder) were aseptically collected, processed and plated onto XLD agar medium.

Only five (2.4%) isolates were identified as Salmonella using conventional biochemical methods and PCR assay based on invA gene.

Out of 5 Salmonella isolates, 4 (80%) were identified as S.

enteritidis using PCR assay based on sefA gene.Antimicrobial susceptibility testing revealed that all isolates of S.

enteritidis were multi-resistant to two or more antimicrobial agents.

Resistance tosulfisoxazole was common across all isolates.

Furthermore, two (50%) penicillin-resistant isolates were tested positive for blaTEM gene using PCR assay.

In addition, β-lactamase activity of these isolates was assessed on penicillin-sensitive strain of S.

aureus (ATCC29213).

Sensitivity of S.

aureus to penicillin was significantly decreased in the presence of beta-lactamase-producing S.enteritidis in comparison with control group.

The current study necessitates further exploration of genetic elements related to antibiotic resistance and underlines the need to track the evolution of β-lactamases in S.

entritidis isolates in Egypt.