Theileria annulata Induced Bilateral Ocular Signs in Cattle and Its Successful Therapeutic Management: A Case Report

Bovine tropical theileriosis is one of the potentially fatal disease of dairy cattle, which is caused by hemoparasite Theleria annulata. About seven years old cross-bred cow was presented with complaint of pyrexia, inappetance, lacrimation and ocular swelling since last 5 days. The clinical examination showed elevated rectal temperature (39.4 °C), mild enlarged pre-scapular lymph nodes, bilateral bulging of temporal fossa, protruded pale and icteric conjunctivae of the eyes with lacrimation and presence of ticks on body. The case was suspected for haemoprotozoan disease. Blood and serum sample were collected for hematological, blood smear examination and molecular examination (PCR), and biochemical analysis respectively. Microscopic examination of blood smear revealed intra-erythrocytic signet ring shaped periplasm of Theileria annulata. Hemato-biochemical examination revealed anemia, hypoproteinemia, hypoalbuminemia and jaundice. Further, PCR assay was done using T. annulata-specific primer pair, Cyto b1 gene targeting the amplicon of 312 bp showed specific band on Gel-electrophoresis. Therapeutic regimen was started with Buparvaquone @ 2.5 mg/kg body weight IM single dose followed by Oxytetracycline @ 10 mg/kg body weight IV in 500 ml of NS for 5 days and Prednisolone @ 0.25 mg/kg body weight IM for 3 days along with supportive therapy. The cattle well responded to the therapy and complete regression of ocular signs was observed within one week of treatment.