Molecular detection of Salmonella bacteria isolated by PCR from ostriches samples in Sirjan district of Kerman province

Salmonellosis is one of the major common human and animal diseases with wide geographical distribution. The most important sources of Salmonella infection in humans are vegetables, dairy products, marine products, meat products (especially poultry meat), and eggs and their products. Standard methods for the detection of Salmonella species are sensitive but time consuming. Therefore, faster methods in this field are required. PCR is a sensitive and specific method for identification of infectious agents. HilA as a highly protected encoding transcription regulation gene can be used for confirmation of Salmonella. The aim of this study is the identification of Salmonella bacteria in ostrich feces by investigation of hilA gene in genomic DNA using PCR and also evaluation of its specificity in comparison with other common techniques.
Material and 500 ostrich feces samples that have previously been investigated for Salmonella by differential-selective cultivation and biochemical tests were used for study of hilA gene presence test. DNA was extracted from feces samples after solvation of feces in culture medium and incubation in 37 ˚C for 24 hours. Then, PCR was performed by hilA specific primers to investigate presence of hilA gene. The investigation of presence of hilA gene among 500 Sirjan’s ostrich feces samples showed that there are 38 feces samples infected by Salmonella which was in agreement with the results of standard tests for Salmonella. It is noteworthy to mention that hilA gene was present in those samples that Salmonella had been identified by standard tests. The results showed that the investigation of hilA gene by PCR using specific primers could be an alternative method for recognition of Salmonella in poultry facet with high accuracy and speed, and also low costs.