Under the skin, inside the heart: Prevalence of arrhythmias triggered by bovine tick-borne diseases

This study was undertaken at Dr. G.C. Negi College of Veterinary and Animal Sciences, CSKHPKV, Palampur, to investigate the prevalence and electrocardiographic characteristics of cardiac arrhythmias in cattle affected with tick-borne diseases (TBDs). Between April 2024 and August 2025, 616 bovine cases were examined, and 158 (25.64%) were confirmed positive for tick-borne haemoparasites on Giemsa-stained blood smear evaluation. Theileriosis was the predominant infection (15.90%), followed by anaplasmosis (7.95%), mixed infections (1.46%) and babesiosis (0.32%). Of the infected animals, 75 (47.46%) demonstrated distinct ECG abnormalities, comprising 1 case of babesiosis (1.33%), 47 of theileriosis (62.66%), 20 of anaplasmosis (26.66%) and 7 of mixed infection (9.33%). The most frequently recorded arrhythmias included P mitrale (76%), tachycardia (45.33%), arrhythmia (42.66%), wide QRS complexes (41.33%), ST elevation (32%), P pulmonale (30.66%), QT interval shortening (21.33%) and deep QRS complexes (18.66%). Females (98.66%) and cattle aged 1–5 years (70.66%) were most commonly affected. The overall findings highlight the substantial burden of cardiac involvement in TBDs and emphasize the importance of routine ECG assessment for early detection, prognosis and guiding timely therapeutic interventions in clinically suspected cases.