Vet World Vol.13 October-2020 Article-30
Research Article
Veterinary World, 13(10): 2252-2259
https://doi.org/10.14202/vetworld.2020.2252-2259
Current advances in molecular subtyping using multilocus variable number of tandem repeat analysis of Salmonella Enteritidis and Salmonella Typhimurium in Egyptian chickens
2. Department of Bacteriology, Immunology, and Mycology, Faculty of Veterinary Medicine, Benha University, Benha, Egypt.
3. Department of Microbiology, Animal Health Research Institute, Marsa Matruh, Egypt.
Background and Aim: This study aimed to characterize the genetic diversity, evolutionary level, and prevalence of genotypes of common isolates of Salmonella (Salmonella Enteritidis and Salmonella Typhimurium). Using one of the most advanced molecular recognition techniques, multilocus variable number of tandem repeat analysis (MLVA), we characterized the genotype and prevalence of S. Enteritidis and S. Typhimurium.
Materials and Methods: One hundred and twenty-five internal organ samples were collected from the major chicken slaughterhouses in Egypt, and Salmonella species were isolated. PCR was utilized to amplify the IE-1 and Flic-C genes to identify S. Enteritidis and S. Typhimurium DNA, respectively, from Salmonella isolates. MLVA was applied on nine samples of S. Enteritidis DNA and three samples of S. Typhimurium DNA. Six variable number tandem repeat (VNTR) loci (Sal02, Sal04, Sal06, Sal10, Sal20, and Sal23) were amplified.
Results: Of the examined samples (n=125), a total of 12 isolates (9.6%) were either identified as Enteritidis or Typhimurium. PCR-mediated amplification of IE-1 and Flic-C revealed that 75% (n=9) of the 12 Salmonella isolates were S. Enteritidis and 25% (n=3) were S. Typhimurium. The six loci amplified through MLVA had allelic diversity. The most discriminatory heterogenic locus for S. Enteritidis was Sal20. Sal04 and Sal23 were the most discriminatory heterogenic loci for S. Typhimurium. VNTR allelic profile analysis revealed nine unique genotypes for S. Enteritidis and three for S. Typhimurium.
Conclusion: This study was the first to use MLVA analysis to identify S. Enteritidis and S. Typhimurium strains isolated from chickens in Egypt. The molecular typing data reported herein allowed us to characterize the genotypes of S. Enteritidis and S. Typhimurium that are most prevalent in Egyptian chickens. Moreover, this epidemiological information provides valuable insight on how to prevent disease transmission. Moreover, our methods provide an alternative to traditional serotyping techniques that may produce inaccurate strain identifications for organisms with rough lipopolysaccharide structures. Keywords: lipopolysaccharides, multilocus variable number of tandem repeat analysis, Salmonella, serotyping.
Keywords: lipopolysaccharides, multilocus variable number of tandem repeat analysis, Salmonella, serotyping.
How to cite this article: Hassan WMM, El Tawab AAA, El-Shannat SM (2020) Current advances in molecular subtyping using multilocus variable number of tandem repeat analysis of Salmonella Enteritidis and Salmonella Typhimurium in Egyptian chickens, Veterinary World, 13(10): 2252-2259.
Received: 08-06-2020 Accepted: 21-09-2020 Published online: 28-10-2020
Corresponding author: Sara M. El-Shannat E-mail: saramvet@yahoo.com
DOI: 10.14202/vetworld.2020.2252-2259
Copyright: Hassan WMM, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.