Detection of Enterotoxin Genes A & B of Staphylococcus aureus strains isolated from raw milk and mastitic milk of dairy cattle herds of Tehran province

Subject Areas : clinical veterinary science

Sepideh Vali ¹ , Farhad Moosakhani ² , Arya Badiei ³ , Ali reza Jamali ⁴ , Samira Ghalambor Dezfoui ⁵

1 - Department of food science, Science and Research of Kurdistan- Sanandaj Branch, Islamic Azad University, Sanandaj, Iran
2 - Department of Pathobiology, Faculty of Veterinary Medicine, Karaj Branch, Islamic Azad University, Karaj, Iran
3 - Department of Clinical Sciences, Faculty of Veterinary Medicine, Karaj Branch, Islamic Azad University, Karaj, Iran
4 - Diagnosis Veterinary laboratory-Mabna , Karaj, Iran
5 - Technical deputy of Alborz province veterinary directorate, Karaj, Iran

Received: 2016-12-18 Accepted : 2016-12-18 Published : 2014-09-23

Keywords: PCR, Staphylococcus aureus, Enterotoxin,

Abstract :

Milk is considered a nutritious food because it contains several important nutrients including proteins and vitamins.Conversely, it can be a vehicle for several pathogenic bacteria such as Staphylococcus aureus. Staphylococcusaureus is one of the most causes of food poisoning (FP) in dairy products. The main etiologic agent of FP isstaphylococcal enterotoxins (SE). There are different types of SE, but type A (SEA) and type B (SEB) are the mostimportant types.The aim of the present study was detection of enterotoxin genes A&B of staphylococcus aureus strains isolatedfrom raw milk of dairy cattle herds of Tehran province. In the current study, 40 samples of raw milk and mastitismilk were transported to the laboratory under sterile conditions and were assessed. Samples were cultured andidentifed by routine bacteriological methods. The isolated bacteria were evaluated by PCR tests for diagnosisof the gene encoding of SEA and SEB.The PCR results showed that(%25) of Staphylococcus aureus isolatespossessed the SEA gene,(%15) had the SEB. Therefor heating has no effect on dairy products contaminated byenterotoxins and gastritis may occur in a short period of time. As PCR is a rapid, sensitive, specifc and inexpensivemethod, we suggest that it can be replaced to traditionally assays for detecting SE.