Journal of Advances in Biology & Biotechnology

Animals recovering from acute infection often become carriers, serving as a potential source of infection for susceptible healthy animals. Early diagnosis, prompt treatment, and effective control measures are essential to reduce mortality and production losses associated with the disease. The present study on bovine theileriosis was conducted in and around Bidar district of Karnataka with an aim to determine the disease prevalence using retrospective (April 2021–March 2024) and prospective (April 2024–March 2025) study. The diagnosis was based on clinical signs of pyrexia, lymph-node enlargement, tick infestation suggestive of theileriosis, blood smear examination and molecular diagnosis (PCR). A total of 1478 cattle were examined, of which 116 were positive, with an overall prevalence of 7.85%. Retrospective analysis showed a lower prevalence (2.93%) compared to a significantly higher prevalence (16.79%) in the prospective study, indicating improved detection through combined clinical, microscopic examination of Giemsa-stained blood smears, and PCR-based diagnostic methods.Higher prevalence was observed in female cattle and crossbred animals, particularly Jersey crossbreds, although differences were statistically non-significant (p > 0.05). Age-wise analysis revealed a significant association (p < 0.05), with higher prevalence in calves (<2 years) and older animals (>6 years). Seasonally, the disease was more prevalent during summer, though it occurred throughout the year.The study confirms that bovine theileriosis is endemicin the region and shows the importance of molecular diagnostics for accurate detection. Implementation of strategic tick control and routine screening is essential to reduce economic losses and improve cattle health.