Screening of Blood Parasites in Australian Wild Deer

Wild animals are natural reservoir hosts for a variety of pathogens, and such is the case for deer (family Cervidae). Deer were introduced to Australia 150 years ago for farming and game, but wild deer populations have expanded considerably in recent years, posing increasing threats to biodiversity, agriculture and public health. There are few data currently available on pathogens that Australian wild deer carry or whether these organisms pose biosecurity threats to humans, wildlife, livestock or other domestic animals. To address this knowledge gap, we tested for the presence of seven parasitic genera in 243 blood samples collected from four wild deer species in eastern Australia. Blood samples were tested by PCR for the presence of Plasmodium, Trypanosoma, Babesia, Theileria, Toxoplasma, Sarcocystis and Neospora DNA. No amplification was obtained for either the 18S rRNA (or the cytochrome b gene in the case of Plasmodium) of the seven selected parasitic genera, suggesting that wild deer in eastern Australia currently pose little risk as vectors of these parasites to livestock and humans. This survey represents the first molecular study of its type in Australian deer and provides important baseline information about the health status of these animals.