Toxoplasma gondii in Florida Manatees (Trichechus manatus latirostris)
IAAAM 2016
Heidi M. Wyrosdick1,2*+; Richard Gerhold2; Chunlei Su3; Martine de Wit4; Alycia Chapman2; Jessica Martinez1,2; Debra L. Miller1,2; Robert Bonde5
1Center for Wildlife Health, Department of Forestry, Wildlife, and Fisheries, University of Tennessee, Knoxville, TN, USA; 2Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN, USA; 3Department of Microbiology, University of Tennessee, Knoxville, TN, USA; 4Marine Mammal Pathobiology Laboratory, Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, St. Petersburg, FL, USA; 5Wetland and Aquatic Research Center, US Geological Survey, Gainesville, FL, USA


Toxoplasma gondii is a protozoan parasite of felids recently reported to cause mortality in Antillean manatees (Trichechus manatus manatus) in Puerto Rico.1 Toxoplasmosis is well documented in marine mammals causing disease in a range of severity.2-8 Prior to 2015, there were only two reports of disseminated toxoplasmosis in Antillean and Florida manatees (Trichechus manatus latirostris).1,9 Our study is an expansion on the most recent report of the seroprevalence of T. gondii in Florida manatees and the first attempt to determine an association between toxoplasmosis in manatees and free-roaming cats.10 As the only definitive host known to shed T. gondii oocysts, wild and domestic felids were hypothesized as potential contamination sources in our study. The objectives of the study are to determine prevalence of T. gondii in Florida manatees and free-roaming cats in Citrus County, Florida, and to compare the T. gondii genotypes between the two populations. Potential transmission dynamics will be presented based on these results. Sera or plasma from one hundred and eighty live-captured manatees and serosanguinous fluid collected opportunistically at necropsy from stranded manatees were tested using the Modified Agglutination Test (MAT) to determine seroprevalence of T. gondii. Free-roaming cat fecal samples were tested by centrifugal floatation for T. gondii oocysts to determine parasite prevalence. Preliminary results include 88 manatee plasma samples negative for T. gondii antibodies and no T. gondii oocysts detected in 40 cat fecal samples tested to date. Testing of remaining samples is ongoing and final results will be presented.


A big thanks to Mr. and Mrs. Lovering for facilitating the feral cat collections and travel assistance. Another big thanks to Lauren Smith for facilitating the introductions that led to the great collaborations between the three institutions in this study. Also, a special thanks to Dr. John Schaefer and Dr. Sharon Patton for their expert assistance with the project's design and methodology. Finally, we would like to thank the USFWS for their assistance in securing the necessary permits for the project and the University of Tennessee Department of Biomedical and Diagnostic Sciences for funding to complete testing.

* Presenting author
+ Student presenter

Literature Cited

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10. Smith LN, de Wit M, Rotstein DS, Francis-Floyd R, Walsh MT, Waltzek TB, Wellenhan JFX, Gerhold R, Su C, Chapman AE. Disseminated toxoplasmosis and serologic survey for Toxoplasma gondii in the wild Florida manatee (Trichechus manatus latirostris). In: Proceedings from the 5th Florida Marine Mammal Health Conference; June 2–4, 2015; Gainesville, FL.


Speaker Information
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Heidi M. Wyrosdick, Student
Center for Wildlife Health
Department of Forestry, Wildlife, and Fisheries
University of Tennessee
Knoxville, TN, USA

Department of Biomedical and Diagnostic Sciences
College of Veterinary Medicine
University of Tennessee
Knoxville, TN, USA

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