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Theileria orientalis: a review
J G Watts1, M C Playford2, K L Hickey1
1a Ministry for Primary Industries , PO Box 2526, Wellington , New Zealand.
New Zealand Veterinary Journal
|July 7, 2015
Summary
Theileria orientalis causes mild theileriosis in cattle by destroying red blood cells. Understanding its impact is crucial for managing this economically important parasite in livestock.
Area of Science:
- Veterinary Parasitology
- Protozoology
- Animal Health
Background:
- Theileria orientalis, historically known as T. sergenti and T. buffeli, causes benign theileriosis in cattle.
- Unlike other Theileria species, T. orientalis schizonts do not induce lymphoproliferation or transformation.
- The exact mechanisms of anemia in infected cattle remain unclear and likely multifactorial.
Purpose of the Study:
- To summarize the characteristics and economic impact of Theileria orientalis infection in cattle.
- To highlight the clinical signs and diagnostic indicators associated with theileriosis.
- To emphasize the need for increased awareness and management strategies for T. orientalis.
Main Methods:
- Literature review of Theileria orientalis (T. sergenti, T. buffeli) in cattle.
- Analysis of pathogenesis, clinical manifestations, and economic significance.
- Identification of risk factors and management considerations.
Main Results:
- T. orientalis primarily causes anemia through erythrocyte destruction.
- Clinical signs include weakness, reluctance to move, abortion, pallor, pyrexia, and increased heart/respiratory rates.
- The parasite poses an economic threat in New Zealand, Australia, and Japan, particularly for naive or stressed cattle.
Conclusions:
- Theileria orientalis is an economically significant cattle parasite, causing benign theileriosis.
- Early recognition of non-specific clinical signs is important for timely intervention.
- Effective management requires increased awareness of risks, especially during animal introductions and periods of stress.
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