Characterisation of pouch secretions from breeding Tasmanian devils

Tasmanian devils (Sarcophilus harrisii), like all marsupials, give birth to altricial young. Here we employ proteomic analysis to identify components of devil pouch secretions that may contribute to offspring survival and development. Proteins were extracted from five samples and analysed by liquid chromatography-tandem mass spectrometry. Peptide-level evidence revealed proteins involved in a diverse set of immune pathways, including those mediating iron-ion transport, defence responses to bacteria, innate immune responses, and antigen processing. A core set of 200 proteins was identified across at least three samples, 63 of which were associated with antimicrobial or immunoregulatory functions. These included immunoglobulins, components of complement and the coagulation cascade, and antimicrobial proteins and peptides. These findings provide preliminary evidence that the Tasmanian devil's pouch secretions could be involved in microbiome restructuring during lactation through their immune protein content. Moreover, the data indicate that these proteins may act synergistically in pathways triggered by immune challenges or physiological stress.