EC Microbiology

Theileriosis is caused by a haemoprotozoan of the genus Theileria. The present study reports theileriosis in captive sambar deer (Rusa unicolor) and spotted deer (Cervus axis or Axis axis) in Bannerghatta Biological Park, Bengaluru. Postmortem examination revealed severe anemia, gelatinization of body fat, lymph node enlargement all over the body, pale spleen with accumulation of straw- colored fluid in the abdominal and thoracic cavity. In few animals, hemorrhages with punched out ulcers were observed on abomasal mucosa. Hematological profiling of infected animals showed characteristic indicators of anemia, hypoproteinemia, thrombocytopenia, low hemoglobin and packed cell volume, lower white blood cell counts reflecting lymphocytopenia with lower erythrocyte counts. Liver specific enzymes estimation indicated biliary or hepatocellular injury, while total bilirubin level was increased reflecting hemolysis and impaired liver clearance. Additionally, serum total protein level was decreased mainly due to hypoalbuminemia. These alterations collectively suggest compromised liver function, often secondary to systemic effects of theileriosis, such as hemolysis and inflammation. Theilerial schizonts were observed in erythrocytes and leucocytes in blood smear. For further confirmation, DNA isolated from blood was subjected to PCR and found positive for Theileria spp. The treatment was done for all the deer in the safari with tetracycline powder, tick control measures using ivermectin suspension along with administration of liver tonic. The animals responded to the treatment with reduction in mortalities.

Keywords: Captive; PCR; Sambar Deer; Spotted Deer; Theileriosis

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