The first finding of and (Nematoda) in feral fallow deer () in Australia.

Feral deer are widespread throughout Australia with the capacity to impact livestock production transmission of parasites. Samples of (fallow deer), (sambar deer), (red deer) and an unidentified deer were sourced from various locations in south-eastern Australia for examination for parasites. Adult nematodes were collected from the lungs of all deer species across four separate geographical locations. The nematodes were identified as species of through both morphological and molecular means. Species identification based on morphological features was difficult, with many measurements from described species overlapping. Molecular analyses targeting three markers, namely 18S rRNA, ITS2, and cox1 revealed the presence of two distinct species: and . These are the first genetically confirmed reports of species of in feral deer in Australia, and although cross-transmission of species of with livestock has not yet been reported, it cannot be completely discounted without further research.