Theileria species undergo cyclical development in ticks to produce sporozoites, which are subsequently injected into mammals to mature into schizonts in leucocytes and piroplasm in erythrocytes. A total of 146 clinically suspected cattle exhibiting anorexia, persistent high fever, enlarged lymph nodes, anemia, dullness, and lethargy were screened using Giemsa-stained blood smear examination and polymerase chain reaction (PCR). Out of 146 animals examined, 36 were confirmed positive by PCR, indicating an overall prevalence of 24.65%, whereas blood smear examination detected 30 positive cases (20.54%). The higher detection rate by PCR confirmed its superior sensitivity in diagnosing Theileria infection, especially in cases with low parasitemia. Theileria was higher in unorganized farms (28.57%) compared to organized farms (21.68%). Age-wise analysis showed the highest prevalence in cattle above 3 years (30.12%), followed by 1–3 years (18.18%) and calves below 1 year (12.5%). Further, it was more prevalent in females (27.27%) compared to males (12.00%) while its susceptibility in Holstein Friesian crossbred cattle (27.10%) was maximum, followed by Jersey crossbred (20.83%), and lowest (13.33%) was in indigenous cattle. Clinically affected animals predominantly exhibited pyrexia (100%), enlarged lymph nodes (88.88%), pale conjunctival mucous membranes (88.88%), reduced appetite (88.88%), tick infestation (77.77%), respiratory distress (83.33%), nasal discharge (69.44%), and diarrhea (33.33%).
Sangekar et al. (2026) studied this question.