Location: Animal Parasitic Diseases LaboratoryTitle: Bobcat (Lynx rufus) as a new natural intermediate host for Sarcocystis neurona
|VERMA, SHIV - Non ARS Employee|
|CALERO-BERNAL, RAFAEL - Non ARS Employee|
|LOVALLO, MATTHEW - Pennsylvania Game Commission, Bureau Of Wildlife Management|
|SWEENY, AMY - National Instiute Of Allergy And Infectious Diseases (NIAID, NIH)|
|GRIGG, MICHAEL - National Instiute Of Allergy And Infectious Diseases (NIAID, NIH)|
Submitted to: Veterinary Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/8/2015
Publication Date: 7/1/2015
Citation: Verma, S., Calero-Bernal, R., Lovallo, M., Sweeny, A., Grigg, M., Dubey, J.P. 2015. Bobcat (Lynx rufus) as a new natural intermediate host for Sarcocystis neurona. Veterinary Parasitology. doi: 10.1016/j.vetpar.2015.06.007.
Interpretive Summary: Sarcocystis neurona is a single celled parasite previously misidentified as Toxoplasma gondii. It causes a fatal illness in horses and several other species of animals. The clinical syndrome was called “Equine Protozoal Myeloencephalitis” before ARS researchers in collaboration with scientists from several universities identified, isolated it, and named it Sarcocystis neurona in 1991. The host range for S. neurona keeps expanding and this parasite is now recognized as a major cause of fatal neurological disease in various mammals, including sea otters. The parasite is not yet known to cause neurological disease in human beings, but the public health importance of this infection deserves greater scrutiny, especially in light of the cerebral infections that can occur in immune-compromised people infected with this parasite’s relative, T. gondii. In the present paper authors found a very high prevalence of S. neurona in bobcats from rural Mississppi; a new host for this parasite. This paper should be of interest to biologists, parasitologists, and veterinarians.
Technical Abstract: The protozoan Sarcocystis neurona is an important cause of severe clinical disease of horses (called equine protozoal myeloencephalitis, EPM), marine mammals, companion animals, and several species of wildlife animals in the Americas. The Virginia opossum (Didelphis virginiana) is its definitive host in the USA and other animals act as intermediate or aberrant hosts. Here we report the bobcat (Lynx rufus) as a new intermediate host for S. neurona. Samples of tongue and heart from 35 bobcats hunted for fur and food from Mississippi State, USA in February, 2014 were used for the present study. Muscles were examined for Sarcocystis infection by microscopic examination of either unfixed muscle squash preparations or pepsin digests, by histopathology of fixed samples, and by molecular methods. Sarcocystislike bradyzoites were found in digests of 14 hearts and 10 tongues of 35 bobcats. In histological sections, sarcocysts were found in 26 of 35 bobcats. S. neurona-like sarcocysts were seen in unstained muscle squash of tongue of two bobcats and PCR-DNA sequencing identified them definitively as S. neurona. DNA extracted from bradyzoites obtained from tongue and heart muscle digests was analyzed by PCR-DNA sequencing at the ITS1 locus. Results indicated the presence of S. neurona in 26 of 35 samples. Sequences identical to S. dayspi were identified in 3 bobcats, 2 of which were also infected with S. neurona. The high prevalence of S. neurona sarcocysts infecting bobcat muscle identified an efficient sylvatic cycle in remote regions of Mississippi with the bobcat as a relevant intermediate host.