Evaluation of hygiene Lighvan cheese aspects regarding Lactococcus garvieae bacteria relying on culture-based and molecular methods

One of the pathogenic bacteria species in the genus of Lactococcus is Lactococcus garvieae. It causes human disease (endocarditis) and mastitis in dairy cows to appear. the presence of these bacteria in the raw milk products like Lighvan cheese was reported. Lighvan cheese is a traditionalcheese which is made from raw sheep's milk. In this study, at first, 1500 colonies similar to Lactococcal genera isolated from different sources such as fresh grass, fresh milk, curd, fresh cheese and ripened cheese according to colony morphology. Then, the 625 isolates were selected by gram stain. Thebiochemical tests carried out to select 60 isolates of Lactococcal genus and the PCR was used to determine the16S rRNA gene sequence region to identify species. Based on molecular identification 50 species, were belonged to the Lactococcal genera and finally two species of Lactococcus were Lactococcus garvieae, According to the results, the presence of two species of Lactococcus garvieae (fresh milk and curd) wasdemonstrated in the early stages of Lighvan cheese production, But, there was no presence of the bacteria in fresh cheese and ripened cheese.

Keywords:

16S rRNA , biochemical tests , Lactococcus garvieae , Lighvan cheese , pathogenic