Kafkas Üniversitesi Veteriner Fakültesi Dergisi 2026 , Vol 32 , Issue 4
Molecular Identification, Typing, and Virulence Gene Profiling of Salmonella Isolates Recovered from Cattle and Buffaloes in Egypt
Amany Dieb BAHR1, Hend Mohsen AUDA1, Yousef Adel SOLIMAN2, Michael Rasmy FAKHRY2, Maha Abo El-naga GAMAL2, Mohamed Gomaa SEADAWY3, Eman Mohamed Samy ELNAGAR4, Emil Saad ABDEL MASSIEH1
1Department of Medicine and Infectious Diseases, Faculty of Veterinary Medicine, Cairo University, 12211, Giza, EGYPT
2Biotechnology Department, Central Laboratory for Evaluation of Veterinary Biologics, Agriculture Research Center (ARC), EGYPT
3Biodefense Center for Infectious and Emerging Diseases, Ministry of Defence (MOD), EGYPT
4Department of Genetic Engineering, Veterinary Serum and Vaccine Research Institute (VSVRI), Agriculture Research Center (ARC), EGYPT DOI : 10.9775/kvfd.2026.37051 Salmonella is a major cause of diarrhea in cattle and buffaloes. This study aimed to isolate and biochemically identify Salmonella species from faeces of cattle and buffaloes, confirm and type isolated Salmonella species molecularly, determine Salmonella infection-associated risk factors, and detect selected virulence genes. A total of 123 fecal samples were collected from cattle and buffaloes from different Egyptian governorates. All samples were processed using standard culture methods, followed by biochemical identification using conventional methods and the VITEK-2 System, with confirmation by qPCR. Conventional PCR was also used for Salmonella serovar identification and detection of the virulence genes spvB, spvC, spvR, and pefA. Bacteriological examinations revealed 13 Salmonella isolates (10.57%); however, the VITEK-2 identification system detected only 12. The qPCR confirmed that 13 were positive for Salmonella. Conventional PCR demonstrated that all 13 Salmonella isolates were of the Typhimurium serovar. Salmonella isolation was significantly higher in diarrheic animals and in animals younger than 3 months (P<0.05), while species, sex, season, and geographic location had no significant effect (P>0.05). Out of 13 S. Typhimurium isolates, 8 isolates tested positive for spvC, 7 for both spvB and pefA, and 5 for spvR, suggesting their limited role in the pathogenesis of diarrhea. This study concluded that qPCR showed higher detection performance for Salmonella isolates than the VITEK-2 system. Keywords : Cattle and buffaloes, Molecular typing, qPCR, Salmonella, Virulence genes, VITEK-2