Does anaerobic bacterial antibiosis decrease fungal diversity in oral necrobacillosis disease?

Oral necrobacillosis (ON) is a model polymicrobial disease that affects macropods in captivity and livestock. Several studies in humans and animals have focused mainly on the bacterial etiology of this disease with little or no information on the role/association of fungi with ON. Using a Polymerase Chain Reaction–Denaturing Gradient Gel Electrophoresis (PCR–DGGE) assay and statistical analysis of the fungal community structure in healthy and disease groups, a reduction in the species diversity and drastic reduction (>1000 fold) in the fungal population in wallabies with ON was observed. Furthermore, an in vitro assay revealed a potential anaerobic-bacteria antibiosis mechanism in the observed decrease in fungal population in ON and a synergistic bacterial–fungal interaction in wallabies with healthy oral status. This study contributes to our knowledge of the fungal community structure associated with ON and forms the basis for an investigation at an epidemiological scale in order to exploit the clinical potentials of these findings.