Veterinary Research Forum

Abstract American foulbrood (AFB) and European foulbrood (EFB) diseases caused by Paenibacillus larvae and Meliscococcus plutonius are prevalent honeybee brood diseases that pose significant economic challenges to the apiculture industry globally. Antibiotic treatment has led to the emergence of antibiotic-resistant strains, encouraging the search for alternative and safe measures to effectively control these diseases. Honeybee gut microbiomes have proven effects on all spectra of honeybee health by enhancing resistance to several diseases via immune modulation and the production of different antimicrobial metabolites. The major part of the gut microbiota is identified as probiotic bacteria, which are live microorganisms that, when administered in adequate amounts, confer health benefits to the host. Probiotics have shown promising health benefits for honeybees. Honeybee gut probiotics provide protection via the production of different metabolites (postbiotics), such as hydrogen peroxide, vitamins, organic acids, free fatty acids, bacteriocins, neurotransmitters, secreted bio-surfactants, and reactive oxygen species. Vast numbers of these gut bacteria and their postbiotics have wide-spectrum antibacterial effects on AFB and EFB. This review highlights the significance of the honeybee gut microbial community, its probiotic potency, and the role of postbiotic metabolites as safe prophylactic measures for preventing AFB and EFB diseases in honeybees.

Abstract Infecting to Melissococcus plutonius, the primary cause of the European foulbrood (EFB) disease, can be followed by infecting to the secondary bacteria, such as Enterococcus faecalis and Brevibacillus laterosporus. The aim of this research was to diagnose EFB disease by tracking the causes of the disease in apiaries all over Iran. From 260 apiaries, honey bee samples were randomly collected. After samples preparation, the genomic DNA was extracted and specific primers were selected for interested bacteria. Using the conventional polymerase chain reaction (PCR) method for E. faecalis and B. laterosporus and nested-PCR method for M. plutonius, the target fragments were amplified. Desired standard bacteria and distilled water were used as positive and negative controls, respectively. Results showed that out of 260 samples from apiaries, 74 and three samples were positive for E. faecalis and B. laterosporus bacteria, respectively. Also, the results of nested-PCR showed that 58 samples were positive, of which only 12 samples were positive in the evaluation of E. faecalis. Results demonstrated that the highest and the least levels of the infection for M. plutonius and E. faecalis were in the south and east of the country, respectively. Results indicated that sometimes due to the excessive growth of secondary bacteria, the main bacteria can be removed from the environment. Also, findings proposed that those provinces with higher number of populations, followed by higher amount of air pollution, had more infected samples than others.