We explored whether N. defodiens transfer enteric bacteria to their anal secretions and ultimately to a carcass.

Direct transmission of bacteria to subsequent generations highlights the beneficial nature of host-bacteria relationships, and is often mediated by the production of microbe-containing secretions by insects. The objective of this study was to determine if the burying beetle, Nicrophorus defodiens, utilizes anal secretions to transmit adult digestive tract bacteria onto a small vertebrate carcass; thus creating the potential to aid in carcass preservation or pass digestive tract bacteria to their larval offspring. Using high-throughput Illumina sequencing of the 16S rRNA gene, we characterized bacterial communities of adult digestive tracts, the anal secretions, and prepared mouse carcasses. We also examined unprepared carcass bacterial communities as a means to interpret community shifts that take place during carcass preservation. We found a vast reduction in diversity on prepared carcasses after anal secretion application however we found little similarity in bacterial communities among adult digestive tracts, anal secretions, and prepared carcasses, suggesting bacterial communities found in adult digestive tracts do not successfully colonize and achieve dominance on prepared carcasses by way of beetle anal secretions. We concluded that N. defodiens do not transmit their digestive tract bacterial communities to prepared carcasses, but we hypothesize that N. defodiens may be transmitting key microbes to the preserved carcass, and perhaps even ultimately on to larval offspring.