Marcia R S Ilha Resident, Anatomic Pathology College of Veterinary Medicine University of Tennessee Case Number: Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

Signalment 16-month-old male wallaby Ollie Wallaby Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

Historylethargy watery diarrhea difficulty breathing mild uveitis increased ALT, ALP and CK seizures cardiorespiratory arrest pet with access to yard another wallaby died Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

Gross findings Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

Gross findings Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

Gross findings Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

Gross findings Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

Gross findings Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

Histopathology

Histopathology

Histopathology

Histopathology

Morphologic diagnosis Cecum: Diffuse, transmural, marked, subacute, necrotizing typhlitis and gut-associated lymphoid tissue necrosis with intralesional protozoan organisms consistent with Toxoplasma gondii Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

Serology Positive for Toxoplasma gondii [IgG > = 8192 UI/ml (>32 UI/ml positive)] Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

Histopathology similar lesions stomach, small intestine, and colon lymphadenitis of mesenteric lymph nodes myocarditis, adrenalitis and thyroiditis encephalitis plasmacytic uveitis and choroiditis interstitial pneumonia, hepatitis, and splenitis Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

Histopathology

Histopathology Intralesional protozoan organisms consistent with T. gondii stomach heart small intestine adrenal gland colonthyroid gland cecum brain mesenteric lymph nodes eye mesentery interstitial pneumonia, hepatitis, and splenitis (not observed) Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

Immunohistochemistry

Immunohistochemistry

Discussion Wallabies and other Australian marsupials are among the most susceptible species to Toxoplasma gondii Severe acute disease with widespread dissemination of the organism is frequently recognized Contamination with T. gondii oocysts from domestic cats and wild felids is suspected as the main source of infection for herbivorous marsupials In this case, feral cats were occasionally observed in the same area where the wallaby was kept Most reported cases of fatal toxoplasmosis have been described in marsupials in captivity, especially in zoos Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

References Dubey JP et al. Toxoplasmosis in black-faced kangaroos (Macropus fuliginosus melanops). Veterinary Parasitology; 30: Johnson AM et al. Serodiagnosis of acute toxoplasmosis in macropods. Veterinary Parasitology; 34: Miller MA et al. Outbreak of toxoplasmosis in wallabies on an exotic animal farm. J Vet Diagn Invest; 4: Basso W et al. Toxoplasmosis in captive Bennett’s wallabies (Macropus rufogriseus) in Argentina. Veterinary Parasitology; 144: Basso W et al. Toxoplasmosis in captive Bennett’s wallabies (Macropus rufogriseus) in Argentina. Veterinary Parasitology; 144: Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

Acknowledgements Dr. Robert Donnell Dr. Shelley Newman Histopathology Lab Staff, UT UC Davis, IHC Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

Questions?