Hematologic, Plasma Biochemical, and Other Indicators of the Health of Tasmanian Platypuses (Ornithorhynchus anatinus): Predictors of Mucormycosis

The fungal disease, mucormycosis, has affected Tasmanian platypuses for nearly three decades. This study investigates the influences of mucormycosis on the haematological, plasma biochemical and other indicators of health in free-living platypuses across 18 Tasmanian river catchments. Live trapping enabled sampling of 161 (apparently) healthy and six ulcerated, mucormycosis-affected platypuses in 75 rivers and streams between January 2008 and March 2009. There were no obvious differences in any haematological or biochemical measures between healthy and mucormycosis-affected platypuses. However, multivariate analysis revealed that ulceration was associated with living at higher altitudes, low tail fat content (high TFI) and low trypanosome load (TL). There was evidence of overall lymphocytosis and monocytosis in animals from currently mucormycosis affected areas, which suggests some level of immune response to the introduced fungus is now widespread in disease affected catchments. Animals from currently, historically and possibly disease-affected catchments, had lower neutrophil counts, mean cell volumes, plasma alkaline phosphatase (ALP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, and higher plasma gamma-glutamyl transpeptidase (GGT) and platelet counts compared to animals from catchments with no evidence of infection. Reference intervals were generated for all haematological and biochemical measurements. Since this is the most comprehensive, systematic and large-scale assessment of the health of the Tasmanian platypus to date, these references intervals should act as the standard against which all future studies of platypuses in Tasmania should be compared.