SallyAnne L. Ness1,2,3,4,5, Gereon Schares1,2,3,4,5,6, Jeanine Peters‐Kennedy1,2,3,4,5,6, Linda D. Mittel1,2,3,4,5,6, J. P. Dubey1,2,3,4,5,6, Dwight D. Bowman1,2,3,4,5,6, Hussni O. Mohammed1,2,3,4,5,6, Thomas J. Divers1,2,3,4,5,6
1Biomedical Sciences (Peters-Kennedy), College of Veterinary Medicine, Cornell University, Ithaca, NY
2Departments of Clinical Sciences (Ness, Divers), College of Veterinary Medicine, Cornell University, Ithaca, NY
3Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Greifswald, Isle of Riems, Germany (Schares)
4Microbiology and Immunology (Bowman), College of Veterinary Medicine, Cornell University, Ithaca, NY
5Population Medicine and Diagnostic Sciences (Mittel, Mohammed), College of Veterinary Medicine, Cornell University, Ithaca, NY
6United States Department of Agriculture, Washington, United States
Tóm tắt
Besnoitiosis is an emerging infectious disease of donkeys ( Equus asinus) in the United States for which there are currently no serologic methods of diagnosis. A study was performed to evaluate physical examination findings and 3 serologic assays for the detection of Besnoitia bennetti infection in donkeys. A prospective study of 416 donkeys from 6 privately owned herds across 5 U.S. states (New York, Pennsylvania, Vermont, Oregon, and Washington) was performed. Donkeys were examined for clinical lesions suggestive of besnoitiosis and evaluated for antibodies against B. bennetti using a fluorescent antibody test (FAT) and 2 immunoblot assays specific for bradyzoite and tachyzoite antigens, respectively. Donkeys were confirmed to be infected with B. bennetti by histology (cases; n = 32) and were compared to those with no clinical signs of besnoitiosis (controls; n = 384). Identifying clinical lesions in 2 or more locations correctly identified infected donkeys 83% of the time. Donkeys with besnoitiosis had significantly higher FAT titers ( P < 0.001) and numbers of bradyzoite ( P < 0.001) and tachyzoite ( P < 0.001) immunoblot bands than control donkeys. The sensitivity and specificity of the serologic assays for detecting besnoitiosis was 88% and 96% for FAT, 81% and 91% for bradyzoite immunoblot, and 91% and 92% for tachyzoite immunoblot, respectively. Fluorescent antibody and immunoblot assays are effective at identifying donkeys with besnoitiosis and provide a more efficient and less invasive diagnostic alternative to histology.
