Contamination and Molecular Characterization of Salmonella spp. Isolated from Pig Carcasses and Pork Collected from Slaughterhouses and Retail Markets in Thai Binh Province

Date Received: May 26, 2026

Date Accepted: Jun 29, 2026

Date Published: Jun 30, 2026

DOI: https://doi.org/10.31817/vjas.2026.9.2.05

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Issue: Vol. 9 No. 2 (2026): Vietnam Journal of Agricultural Sciences

Section:

ANIMAL SCIENCE – VETERINARY MEDICINE – AQUACULTURE

How to Cite:

Lan, N., Hang, N., Hiep, T., Hoa, T., Linh, P., Quynh, N., … Duc, H. (2026). Contamination and Molecular Characterization of Salmonella spp. Isolated from Pig Carcasses and Pork Collected from Slaughterhouses and Retail Markets in Thai Binh Province. Vietnam Journal of Agricultural Sciences, 9(2), 2975–2985. https://doi.org/10.31817/vjas.2026.9.2.05

Contamination and Molecular Characterization of Salmonella spp. Isolated from Pig Carcasses and Pork Collected from Slaughterhouses and Retail Markets in Thai Binh Province

Nguyen Thi Lan 1 , Nguyen Thi Thu Hang 1 , Tran Hiep 1 , Tran Thi Khanh Hoa 1 , Pham Thuy Linh 1 , Nguyen Thi Huong Quynh 1 , Nguyen Van Thang 1 , Cam Thi Thu Ha 1 , Hoang Minh Son 1   , Hoang Minh Duc (*) 1

  • Corresponding author: [email protected]
  • 1 Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Hanoi 12400, Vietnam

    • Keywords

    Salmonella, virulence gene, ESBLs, pork, carcass, antibiotic resistance

    Abstract


    Pork is considered one of the major vehicles for Salmonella transmission to humans. This study aimed to determine the prevalence, serovar distribution, and virulence gene profiles of Salmonella isolates recovered from pig carcasses and pork in Thai Binh province. A total of 192 samples, comprising carcass swabs and pork samples, were collected from slaughterhouses and wet markets. Salmonella was detected in 22.92% (44/192) of the samples, with prevalence rates of 25.00% (24/96) in slaughterhouses and 20.83% (20/96) in wet markets. Among the 44 Salmonella isolates, only S. Typhimurium (31.82%, 14/44) and S. Virchow (4.55%, 2/44) were identified using the PCR-based serotyping assay targeting five selected serovars, whereas 63.63% (28/44) of the isolates remained untyped. The virulence genes invA, msgA, tolC, lpfC, pagC, and spaN were detected at relatively high frequencies of 100%, 90.91%, 77.27%, 72.73%, 70.45%, and 70.45%, respectively. In contrast, the spvC gene was found in only 4.5% of the isolates, whereas none carried the cdtB gene. The results of ESBL test showed that 27.27% (12/44) of the isolates were ESBL producers carrying blaCTX-M-1, blaCTX-M-9, and blaTEM genes. The detection of ESBL-producing Salmonella in carcasses and pork highlights a potential public health risk and underscores the need for enhanced food safety surveillance and intervention measures to reduce Salmonella contamination.

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