It is also referred as tropical theileriosis and results in fever, enlargement of superficial lymphnodes, anaemia and jaundice.
Etiology: The disease in India is caused by Theileria annulata in cows and buffaloes, and in sheep and goats by T. ovis and T. hirci (details are given in chapter....).
Pathogenesis: In the saliva of ticks, sporozoites are present which enter inside the body of animals by tick infestation and reach into lymphocytes to form schizonts in lymphnodes. (details are given in chapter....).
Clinical signs: The disease occurs in acute form in most of the cases. Initially there is high rise of body temperature which may be intermittent or continuous. The animals reveal inappetance, excessive lacrimation, serous nasal discharge, rapid heartbeat, progressive weakness, marked anaemia and swelling of superficial lymphnodes. The conjunctivae are icteric and had petechial haemorrhages. Haemoglobinuria is not seen but bilirubinaemia and bilirubinuria are present. In diarrhoea often blood is mixed and it has excess mucus. Most of the untreated cases die within 2 weeks due to edema of lungs.
On postmortem examination, pulmonary edema, hyperemia, hydrothorax, emaciation, pale mucus membranes and yellow colouration of tissue are noticed. Spleen, liver and lymphnodes are enlarged while punched ulcers are seen in abomasum and intestine which are pathognomic.
Diagnosis: It is diagnosed by clinical symptoms and confirmed by examination of blood smear prepared at the height of temperature. Smear from lymphnodes may be examined after staining for Koch's blue bodies. Serological tests like capillary agglutination, complement fixation, indirect haemagglutination or ELISA tests are also used for confirmation. Blood examination reveals leukopenia and thrombocytopenia. The disease should be differentiated from anaplasmosis, babesiosis and trypanosomiasis by blood smear examination.
Treatment: Previously, for the treatment of disease chlortetracycline (10-15 mg), rollitetracycline (5-10 mg) or oxytetracycline (10-15 mg/kg body weight) was being used for longer duration. Presently, buparvaquone has been found very effective, if given @ 2.5 mg/kg body weight intramuscularly and repeated after 48 hr. The cost of treatment is high. In addition, use of haematinics and liver tonics is useful in early recovery of case.
Control: A live attenuated vaccine is available against theileriosis, which is given in the calves above 4 months of age. One ml of reconstituted vaccine is given by subcutaneous route and it provides immunity for 1 year.