Molecular Detection of Enterococcus faecalis as a Secondary Agent of European Foulbrood Disease in Honey Samples

Introduction: European foulbrood (EFB) disease is the most important bee larvae disease in honey bees, caused by Melissococcus plutonius, and subsequently the larvae are infected with secondary bacteria such as Enterococcus faecalis, Brevibacillus laterosporus, and Paenibacillus alvei. Therefore, the presence of these secondary bacteria can be considered as a remarkable sign for EFB disease. Since the preparation of honey bee samples for the assessment of apiary health presents principal problems, this research aimed to use honey samples to track E. faecalis as a secondary agent of EFB disease in apiaries all over Iran. Materials & Methods: A total of of ۲۶۰ apiaries were selected, and honey samples were collected during the autumn and winter of ۲۰۲۳. After preparation of the honey samples according to the standard protocol, genomic DNA was extracted from the samples, and then a pair of specific primers was used to amplify the target fragment of E. faecalis using the polymerase chain reaction (PCR) technique. As the positive and negative controls, the standard bacterium and the distilled water were used, respectively. A sensitivity test was performed using specific concentrations of DNA extracted from the standard E. faecalis under the corresponding optimal PCR reaction conditions, and the appropriate concentration was considered for the PCR reaction of the collected samples.Results: PCR results showed that ۱۱۹(۴۶%) of the ۲۶۰ honey samples were positive for E. faecalis. Conclusion: The findings show that the quick and easy use of honey samples for diagnosing E. faecalis can be introduced as an appropriate method to detect this bacterium. Therefore, honey samples can be recommended as a source for the detection of E. faecalis. Also, severe infection of the Iranian apiaries with E. faecalis as an indicator of EFB disease should be recognized as a very significant problem.

کلیدواژه ها:

Enterococcus faecalis ، European foulbrood ، Honey samples ، PCR detection