| Autor: |
Onzere CK; Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA., Herndon DR; Animal Disease Research Unit, USDA-ARS, Pullman, WA 99164, USA., Hassan A; Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA.; Department of Animal Medicine, The Faculty of Veterinary Medicine, The University of Alexandria, Alexandria 21944, Egypt., Oyen K; Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA.; Animal Disease Research Unit, USDA-ARS, Pullman, WA 99164, USA., Poh KC; Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA.; Animal Disease Research Unit, USDA-ARS, Pullman, WA 99164, USA., Scoles GA; United States Department of Agriculture, Agricultural Research Service, Invasive Insect Biocontrol and Behavior Laboratory, Beltsville, MD 20705, USA., Fry LM; Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA.; Animal Disease Research Unit, USDA-ARS, Pullman, WA 99164, USA. |
| Abstrakt: |
Theileria orientalis Ikeda has caused an epidemic of bovine anemia and abortion across several U.S. states. This apicomplexan hemoparasite is transmitted by Haemaphysalis longicornis ticks; however, it is unknown if other North American ticks are competent vectors. Since the disease movement is largely determined by the host tick range(s), the prediction of the T. orientalis spread among U.S. cattle populations requires determination of additional competent tick vectors. Although Rhipicephalus microplus has mostly been eradicated from the U.S., outbreaks in populations occur frequently, and the U.S. remains at risk for reintroduction. Since R. microplus is a vector of Theileria equi and T. orientalis DNA has been detected in R. microplus , the goal of this study was to determine whether R. microplus is a competent vector of T. orientalis . Larval R. microplus were applied to a splenectomized, T. orientalis Ikeda-infected calf for parasite acquisition, removed as molted adults, and applied to two T. orientalis naïve, splenectomized calves for transmission. After 60 days, the naïve calves remained negative for T. orientalis by PCR and cytology. Additionally, T. orientalis was not detected in the salivary glands or larval progeny of acquisition-fed adults. These data suggest that R. microplus is not a competent vector of the U.S. T. orientalis Ikeda isolate. |
