Pathologic and immunohistochemical findings in an outbreak of systemic toxoplasmosis in a mob of red kangaroos

Mariano Carossino, Rudy Bauer, Mark A. Mitchell, Charles O. Cummings, Anke C. Stöhr, Nobuko Wakamatsu, Kimberly Harper, Ingeborg M. Langohr, Kendra Schultz, Maria S. Mitchell, Daniel K. Howe, Udeni B.R. Balasuriya

Research output: Contribution to journalArticlepeer-review

6 Scopus citations


Toxoplasma gondii is a zoonotic protozoan pathogen that infects many endothermic vertebrates, including humans; the domestic cat and other felids serve as the definitive host. Macropodids are considered highly susceptible to toxoplasmosis. Here, we describe the clinical, pathologic, and immunohistochemical findings of an outbreak of systemic toxoplasmosis in a mob of 11 red kangaroos (Macropus rufus), with high morbidity (73%) and mortality (100%) rates. Affected animals had either severe and rapidly deteriorating clinical conditions or sudden death, which was correlated with widespread necrotizing lesions in multiple organs and intralesional T. gondii organisms identified via MIC3-specific immunohistochemistry and confirmed by REP529-specific rtPCR. Quantification of parasites demonstrated the highest parasite density in pulmonary parenchyma compared with other tissues. Our study highlights the continued importance of this severe condition in Australian marsupials.

Original languageEnglish
Pages (from-to)554-565
Number of pages12
JournalJournal of Veterinary Diagnostic Investigation
Issue number3
StatePublished - May 2021

Bibliographical note

Funding Information:
We thank the members of the Histology and Immunohistochemistry sections at the Louisiana Animal Disease Diagnostic Laboratory (LADDL), School of Veterinary Medicine, Louisiana State University for their assistance. We also thank Ms. Michelle Yeargan at the University of Kentucky for her help in generating cell pellet controls. The following reagent was obtained through BEI Resources, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH): Monoclonal Anti-Toxoplasma gondii Micronemal Protein 3, Clone T4 2F3 (produced in vitro), NR-50261. This study was partially supported by Louisiana State University, School of Veterinary Medicine start-up fund (PG 002165) to Dr. Udeni B. R. Balasuriya.

Publisher Copyright:
© 2021 The Author(s).


  • Apicomplexa
  • Toxoplasma gondii
  • histopathology
  • immunohistochemistry
  • red kangaroos
  • toxoplasmosis

ASJC Scopus subject areas

  • Veterinary (all)


Dive into the research topics of 'Pathologic and immunohistochemical findings in an outbreak of systemic toxoplasmosis in a mob of red kangaroos'. Together they form a unique fingerprint.

Cite this