Plasmid Profile and ERIC-PCR Characterization of Salmonella Enteritidis Isolates Recovered from Day-Old Broilers

Document Type : Original Articles

Authors

1 Department of Avian Health and Diseases Faculty of Veterinary Medicine University of Tehran Tehran, Iran

2 Department of Avian Health and Diseases, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran

Abstract

Background: Salmonellosis is widely recognized as an epidemic disease with public health significance. Salmonella Enteritidis has the ability to cause infections in humans and various animals, such as poultry. Salmonella Enteritidis is considered one of the most important and common serovars isolated in different regions of the world.
Objectives: The aims of this study were to characterize 100 Salmonella Enteritidis isolates recovered from day-old broilers with respect to plasmid profile and Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR.
Methods: All Salmonella isolates were recovered from cases referred to our laboratory. Standard bacteriological and molecular procedures were performed for isolation and identification of Salmonella Enteritidis. A commercial kit was used to extract the plasmids. Two primers, ERIC1R and ERIC2, were used for the ERIC-PCR.
Results: Six plasmid profiles were identified among 100 SE isolates, and a plasmid with a molecular weight of greater than 10 kb was observed in all isolates. In ERIC-PCR, seven different profiles were identified with each primer. By using ERIC1R primer, 80% of the isolates belonged to profiles A, B, and G, and the rest distributed among other four profiles. Additionally, using ERIC2 primer, 85% of the isolates belonged to three profiles: D, F, and G, and the rest distributed among other four profiles. When the results of plasmid profiles and ERIC-PCR analysis by using two different primers were combined, 100 SE isolates were divided into 43 groups, with seven groups comprising 54% of the isolates.
Conclusion: This study demonstrated that molecular techniques such as ERIC-PCR and plasmid profile alone have limited power in differentiating between various isolates, and a combination of patterns obtained from multiple techniques will provide greater discriminatory power. This study presented genetic data related to Salmonella Enteritidis isolates, which can be used for a broader epidemiological study at the national level.

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