Student Case Presentation
Bovine Anaplasmosis in the Era of Emerging Hemoparasites: A Fatal Case and Diagnostic Considerations with Theileria orientalis (Ikeda)
| Date/Time: |
8/27/2026 Poster 08
|
| Presenter: |
Tayler Chamberlain |
| Veterinary School: |
OK |
Abstract:
Bovine anaplasmosis, caused by the rickettsial organism Anaplasma marginale, remains a significant disease of cattle worldwide. This case report describes a 6-year-old Maine Anjou cow that presented shortly after purchase with acute lethargy, tachypnea, and pale mucous membranes consistent with severe anemia. Initial stabilization included isolation and minimal handling to reduce stress. Diagnostic evaluation consisted of complete blood count, biochemistry, packed cell volume, total protein, and blood smear analysis.
The PCV was 13% and the blood smear revealed intraerythrocytic inclusion bodies consistent with A. marginale in over 50% of erythrocytes, confirming a diagnosis of acute anaplasmosis. Given the severity of anemia, a whole blood transfusion was initiated using a donor cow. The patient collapsed and died shortly after initiating the procedure, highlighting the fulminant nature of the disease.
Anaplasmosis remains of major importance to the cattle industry due to its substantial economic impact and the lifelong carrier state of infected animals. This facilitates ongoing transmission through biological vectors and iatrogenic spread. Losses are associated with mortality, decreased production, and reproductive inefficiency.
The clinical relevance of anaplasmosis is further complicated by the emergence of Theileria orientalis (Ikeda), transmitted by the invasive Haemaphysalis longicornis, which produces overlapping clinical signs including anemia and reduced productivity. This case underscores the importance of early recognition and prompt intervention to improve outcomes as well as decrease economic loss.
