Georgia Veterinary Scholars Program at the UGA College of Veterinary Medicine

The University of Georgia College of Veterinary Medicine

2005 Georgia Veterinary Scholars

Georgia Veterinary Scholar	Faculty Mentor

Staci Murphy University of Georgia Class of 2007	Dr. Michael Yabsley

Molecular Characterization of Piroplasms from Cougars (Puma concolor) in Florida.

Staci M. Murphy* 1, Michael J. Yabsley 1,2, David S. Peterson 2, and Mark W. Cunningham 3. 1Southeastern Cooperative Wildlife Disease Study, and 2Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA, and 3Florida Fish and Wildlife Conservation Commission, Gainesville, FL.

Cytauxzoon felis is a protozoan blood parasite that causes a fatal, febrile illness in domestic cats with documented cases occurring primarily in the south and south-central United States. While the natural history of this parasite is poorly understood, bobcats (Lynx rufus) are considered the natural reservoir and transmission occurs experimentally by a tick vector, Dermacentor variabilis. There is further evidence of persistent, subclinical infections in Florida panthers (Puma concolor coryi) and translocated Texas cougars (Puma concolor stanleyana) in southern Florida. The major goals of this research project were to molecularly confirm the presence of C. felis in cougars from Florida and to further characterize the intraspecies variability between C. felis samples from wild and domestic felids. Blood samples were collected from 39 native Florida panthers and two translocated Texas cougars from 1989-2005. Each sample was screened for the presence of intraerythrocytic piroplasms using a nested polymerase chain reaction for the 18S rRNA gene. Positive samples were further characterized by sequencing the ITS-1 region of the rRNA gene. Piroplasms were detected in 39 (95%) of the cougars. Sequence analysis and restriction enzyme digestion indicate C. felis infection in five of these cougars, and the sequence of the ITS-1 region from three of these felids was 99.4% identical to the ITS-1 region of C. felis from domestic cats. However, restriction enzyme analysis for the remaining 32 piroplasm-positive cougars indicate infection with a piroplasm distinct from C. felis. Two of the cougars were apparently co-infected with both C. felis and the other piroplasm. Phylogenetic analysis of partial 18S rRNA gene sequence (1,534 bases) indicates that this novel piroplasm is closely related to a Babesia species previously detected in Japanese ticks (Ixodes ovatus), and the ITS-1 region of two samples shared only 4.5% identity to C. felis. This study indicates that the majority of cougars in southern Florida are infected with an apparently novel Babesia species and thus may not be important reservoirs of C. felis. Further research is necessary to delineate the potential infectivity and pathogenicity of this novel Babesia to domestic cats.

[Supported by the University of Georgia Research Foundation]