Prevalence of Salmonella spp. in smallholder chicken farms in Hue City
Vol. 135 No. 3B (2026), Original Article
Vol. 135 No. 3B (2026)

Prevalence of Salmonella spp. in smallholder chicken farms in Hue City

Original Article
https://doi.org/10.26459/hueunijard.v135i3B.8143
Published 2026-05-22
Nguyen Thi Quynh Anh
University of Agriculture and Forestry, Hue University, 102 Phung Hung St., Hue, Vietnam
Nguyen Xuan Hoa
University of Agriculture and Forestry, Hue University, 102 Phung Hung St., Hue, Vietnam
Tran Quang Vui
University of Agriculture and Forestry, Hue University, 102 Phung Hung St., Hue, Vietnam
Nguyen Van Chao
University of Agriculture and Forestry, Hue University, 102 Phung Hung St., Hue, Vietnam
Huynh Van Chuong
Institute of Biotechnology, Hue University, Nguyen Đinh Tu St., Hue, Vietnam

Keywords

Chăn nuôi gà nông hộ
môi trường
Salmonella spp.
yếu tố ảnh hưởng
thành phố Huế risk factors
smallholder chicken farming
environment
Salmonella spp.
Hue City

Abstract

This study aimedto determine the prevalence and risk factors associated with the presence of Salmonella spp. in smallholder chicken production under semi-commercial and traditional systems in Hue City. A total of 620 samples were collected from 93 farms located in Phong Dien, Quang Dien, and Phu Vang commune., including cloacal swabs, drinking water, litter, dust, feed, and internal organs. Isolation was performed following the Vietnamese Standard TCVN 10780-1:2017. The isolates were identified using biochemical tests and PCR targeting the invA gene (244 bp). The results showed that 33.71% of samples were positive for Salmonella spp., with the highest detection rate observed in internal organs (58.82%), followed by litter (45.83%) and cloacal swabs (42.23%). Several factors increased the risk of Salmonella infection in chickens in Hue City, including the use of bio-litter bedding (OR=2.96; 95%CI=1.56–5.63; p=0.002), absence of routine disinfection (OR=1.80; 95%CI=1.09–3.21; p=0.0001), wooden or bamboo housing (OR=3.10; 95%CI=1.55–6.36; p=0.002), and lack of technical training among farmers (OR=2.28; 95%CI=1.27–3.88; p=0.0001). All isolated strains were positive for the invA gene, indicating the widespread virulence potential of Salmonella spp. These findings suggest that Salmonella spp. remains a significant hazard in smallholder chicken production systems; therefore, strengthening biosecurity and improving farmer awareness are essential to reduce the circulation of the pathogen.

https://doi.org/10.26459/hueunijard.v135i3B.8143

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