Veterinary and Comparative Biomedical Research

Veterinary and Comparative Biomedical Research

Prevalence of Virulence-Related Genetic Determinants in Corynebacterium pseudotuberculosis Isolated from Suspected Ovine Caseous Lymphadenitis in Kerman Province, Iran

Articles in Press

Document Type : Original Article

Authors
Hossein Ghaderpoor 1
Masoud Ghorbanpoor 1
Azam Mokhtari 1
Mohammad Mehdi Namavari 2
1 Department of Pathobiology, Faculty of Veterinary Medicine, Shahrekord University, Shahrekord, Iran
2 Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization, Shiraz, Iran
10.22103/VCBR.2026.26657.1121
Abstract
Caseous lymphadenitis is a chronic and contagious disease affecting sheep and goats worldwide, caused by Corynebacterium pseudotuberculosis (C. pseudotuberculosis). The pathogenicity of C. pseudotuberculosis is associated with several virulence genes, including pld, hsp60, fagA, fagB, fagC, fagD, spaC, nanH, and sodC. This study aimed to isolate C. pseudotuberculosis from lymph node samples of sheep suspected of caseous lymphadenitis (CLA) in Kerman Province, Iran, and to detect key virulence-associated genes using polymerase chain reaction (PCR). A total of 150 lymph node samples were collected from sheep with suspected CLA. After bacterial culture and purification, identification was supported by biochemical assays such as catalase production, nitrate reduction, urease activity, and the reverse CAMP test with Staphylococcus aureus. Isolates identified as C. pseudotuberculosis were further analyzed by PCR for the presence of pld, hsp60, fagA, fagB, fagC, fagD, spaC, nanH, and sodC virulence genes. Out of 150 samples, 17 were found to be infected with C. pseudotuberculosis. PCR results showed that among the 17 isolates, all isolates (100%) possessed the hsp60, fagA, fagB, fagC, spaC, nanH, and sodC genes; 15 isolates (88.23%) harbored the fagD gene and 14 (82.35%) carried the pld gene;. The high prevalence of multiple virulence genes among the C. pseudotuberculosis isolates highlights their potential role in the pathogenicity of CLA. These gene profiles may also inform future strategies for vaccine development and disease control.
Keywords
Caseous Lymphadenitis
Corynebacterium pseudotuberculosis
PCR
Virulence Factor
Sheep
Subjects
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Veterinary and Comparative Biomedical Research

Articles in Press, Corrected Proof
Available Online from 18 August 2026