1Department of Veterinary Microbiology, West Bengal University of Animal and Fishery Sciences, Belgachia, Kolkata-700 037, West Bengal, India
2ICAR-Reserch Centre for NEH Region, Kolasib-796 081, Mizoram, India
3ICAR-ERS-IVRI, Belgachia, Kolkata-700 037, West Bengal, India
4Department of Veterinary Microbiology, West Bengal University of Animal and Fishery Sciences, Belgachia, Kolkata-700 037, West Bengal, India
5Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur-784 028, Assam, India
6Environmental Biotechnology and Genomics Division, NEERI, Nagpur-440 020, Maharashtra, India
College of Veterinary Sciences and Animal Husbandry, Central Agricultural University Imphal, Selesih, Aizawl-796 015, Mizoram, India
* Corresponding Author: T.K. Dutta, Department of Veterinary Microbiology, Central Agricultural University-Imphal, Selesih, Aizawl-796 014, Mizoram, India, Email: tapandutta@rediffmail.com
Online published on 30 June, 2020.
Salmonella has emerged as one of the most important food-borne pathogens for humans as well as animals and the ability of biofilm formation by these bacteria has further aided their survival in unfavorable environment. Characterization of these biofilm producing bacteria isolated from pigs and chicken may lead to formulation of strategies for prevention and control of Salmonella infections. Therefore, the present study was conducted to isolate Salmonella from pigs and poultry of Mizoram, determine their biofilm producing ability by phenotypic and genotypic methods along with their virulence and antimicrobial resistance properties. A total of 15 Salmonella spp. (pig=9, poultry=6) was isolated from 100 faecal samples from pigs and 50 cloacal swabs from poultry and biofilm producing ability of the isolates was determined by microtiter plate assay. A total of 10 (66.67%) isolates were found to be biofilm producer. All the biofilm producing bacterial isolates were investigated for antimicrobial sensitivity and distribution of selected biofilm associated genes (csgA, csgD and adrA), virulence genes (invA, stn and sefA) and antimicrobial resistance (AMR) genes (blaTEM, blaSHV and blaCTX-M). The most prevalent resistance was found against ceftazidime (80%), ceftriaxone (80%), cefixime (70%), cefotaxime (70%), gentamicin (70%), cotrimoxazole (60%) and ampicillin (60%). A total of 7 (70%) isolates were resistant to at least three different classes of antimicrobial agents and considered as multidrug resistant. All the isolates were positive for adrA (100%) but negative for csgA and csgD genes. The most frequent virulence gene was invA (100%) and stn (100%). Among the AMR genes, blaTEM (60%) was found to be the major AMR determinants. Moreover, a total of 7 Salmonella isolates were positive for at least one of t biofilm associated genes, virulence genes and AMR genes.
Antimicrobial resistance, Biofilm, Pig, Poultry, Salmonella, Virulence genes
