علی اصغر بهاری

Background: Salmonellas are gram-negative facultative anaerobic bacteria that cause serious gastrointestinal disease in humans and animals. As a result, detection of these bacteria is very important. The objective of the present study was to investigate Salmonella infections in fecal samples obtained from cattle farms in Hamedan province of Iran. Methods: A total of 120 fecal samples were collected from cattle herds and cultured in Rappaport transport medium. Then, Salmonella isolates were characterized according to the growth specifications on differential media including Xylose-lysine deoxycholate (XLD), Citrate, Triple sugar iron (TSI) agar and SIM. The identity of the isolates was also confirmed using a species-specific PCR which targeted invA gene. Conclusion: Our findings confirmed that Salmonella infection was present in dairy farms of Hamedan province for the first time. Hence, it is suggested to take appropriate measures to control this infection in the area. Besides, possible circulating of such bacteria between the animals and humans could be a public health concern because Salmonellas are considered as important zoonotic pathogens. Results: According to the cultural and biochemical features, 22 (18.33%) out of 120 examined fecal samples were infected with Salmonella spp. In addition, all of these 22 isolates were genetically confirmed to be Sallmonella using invA-PCR assay. Keywords: Salmonella, fecal samples, cattle, PCR.