Molecular survey in relation to risk factors and haemato-biochemical alteration in Theileria equi infection of equines in Punjab Province, India

Equine piroplasmosis caused by Theileria equi, an apicomplexan intracellular haemoprotozoan parasite effects equids throughout the world. Current investigation is the first detailed epidemiological survey report based on conventional (blood smear) and primary polymerase chain reaction (PCR) for the detection of T. equi on 464 equids (426 horses and 38 donkeys/mules) in Punjab province of India. PCR targeting 18S rRNA gene of T. equi produced high fidelity 709bp amplification products with 100% concordance with blood films. The prevalence of infection was proportional (P≤0.01) to temperature and aridness of the regions, which turned out to be the most important physical factor pertaining to T. equi infection. Spatial distribution analysis revealed an increasing trend of disease prevalence from north-eastern to south-western region of Punjab by both the techniques. Haemato-biochemical analysis revealed significant decrease in total erythrocyte count and haemoglobin; and increase in mean corpuscular haemoglobin, serum globulin, glucose, creatinine, aspartate aminotransferase and bilirubin levels (P≤0.05). This study divulges the endemicity of equine theileriosis in Punjab with the prominence of various odds of infection, emphasising the pathophysiological manifestation associated with latent infection of T. equi detectable by PCR.