AN OUTBREAK OF THEILERIA ANNULATA - INFECTIONS AMONG FRESIAN CATTLE AT AL GASSIM AREA OF SAUDI ARABIA

MAGZOUB, M.; OMER, O.H.; HAROUN, E.M.; MOTTELIB, A.A.

doi:10.21608/avmj.1992.186648

AN OUTBREAK OF THEILERIA ANNULATA - INFECTIONS AMONG FRESIAN CATTLE AT AL GASSIM AREA OF SAUDI ARABIA

Document Type : Research article

Authors

10.21608/avmj.1992.186648

Abstract

Six fatality cases out of twenty three infected fresian cattle, in a dairy farm in an outskirt of Burreidah city, were reported to the Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, King Saud University. Field observations showed clinical signs suggestive of acute Theileria infection marked by fever, reaching up to 41 C, respiratory distresses, swellings of the superficial lymph nodes and a black diarrhoea. Almost all the animals were heavily infested with ticks. Mature and immature specimens were quite numerous specially on the ear regions of cattle. They were identified as Hyalomma anatolicum anatolicum. Quick diagnosis was made by the demonstration of schizonts and erythrocytic forms of Theileria annulata in both Leishman and Giemsa - stained blood smears. The erythrocytic forms were rodlike, oval, comma-shap < /strong>ed and crescent-shaped. The rate of ap < /strong>pearance of these forms was 30%. Schizonts were irregular in shape and quite numerous in the lymphocytes of the circulating blood. Fourteen out of seventeen clinical cases were treated with Clexon drug and showed complete recovery.