Clinical Picture and Haemogram Profile Associated with Theileria annulata Infection in Cattle before and after Therapeutic Intervention

Bovine theileriosis listed one of the tick-borne diseases of crucial concern worldwide.. The objectives of this study were to investigate the occurrence of tropical theileriosis in a farm of cattle demonstrating acute manifestations by Giemsa stained blood smears and Tams1gene based polymerase chain reaction (Tams-1 PCR). Moreover, to follow up the treatment with buparvaquone and long-acting oxytetracycline on the clinical, parasitological and hematological profile of infected cattle. Blood samples were collected from cattle (n=25) suspecting Theileria annulata (T. annulata) infection and healthy ones (n = 10; clinically and parasitologically free) in Sharkia Governorate Egypt, during JulyAugust 2019. Fever (40-41°C), superficial lymph nodes enlargement, corneal opacity, and cases of non-specific abortion were the most manifestations recognized. The microscopic examination of blood smears (n=25) showed intracellular signet ring piroplasms which, confirmed using Tams1gene based PCR that identified Theileria parasites as T. annulata. Haemogram revealed normocytic normochromic anemia, meanwhile, the total leukocyte count (TLC) and lymphocytes significantly increased (P ≤0. 05) compared to the control ones using T-test. The cure rate in all treated cattle was (88%; 22 / 25) two weeks after the treatment. A rapid decrease in parasitemia in adults and young cattle to 0.5%, and 7%, respectively one week after treatment, and a significant increase in hematocrit percent and erythrocyte count, as well as macrocytic hypochromic anemia, was recorded two weeks from the beginning of the therapy. In conclusion, the response of Infection with T. annulata plays a vital role in occurrence of anemia and in changing blood parameters. Buparvaquone and oxytetracycline are indicated in the treatment of acute theileriosis together with iron supplements.