Cross-sectional study on prevalence of theileriosis in Kendrapada sheep, Odisha

Abstract

Abstract Ovine theileriosis represents a significant threat to both animal welfare and global agricultural productivity, particularly impacting economically disadvantaged farmers. Vector-borne haemoparasitic diseases like theileriosis have a profound effect on the health of livestock, leading to increased illness and mortality, especially in the coastal regions of Odisha. This research aimed to investigate and comprehend the prevalence, clinical manifestations, hematological and biochemical parameters, as well as molecular aspects of theileriosis in sheep from Kendrapada. Among 148 blood samples collected from Kendrapada sheep across four blocks, 13% tested positive for theileriosis, indicating a notable prevalence. The prevalence rate was highest among sheep aged 1–4 years (19%), followed by those younger than 1 year (17.9%) and older than 4 years (13.3%). Female sheep exhibited a higher prevalence (19%) compared to males (16%). Block-wise prevalence was highest in Aul (27.9%), followed by Marshaghai (19.4%), Kendrapada (16.1%), and Derabish (5.88%). Hematological analysis revealed deviations in parameters such as hemoglobin, total erythrocyte count, total leukocyte count, and mean corpuscular volume, while packed cell volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and differential leukocyte count remained within normal ranges. Significant differences (P < 0.05) were observed in various parameters between Theileria-positive and negative sheep. However, there were no substantial variations noted among different age groups and genders of Theileria-positive sheep. PCR analysis identified an overall incidence of theileriosis at 17.57% in the study population, with sequences closely resembling Theileria luwenshuni isolates. This study confirms the high variability of the 18S small subunit rRNA gene among Theileria spp.