Theileriosis (Tick Fever) — The Silent Killer of Dairy Cows
1.Introduction Theileriosis is an extremely destructive tick-borne protozoal illness mainly caused by Theileria annulata . One of the most economically striking diseases is the spread of Theileria annulata in the dairy and livestock sector of Pakistan, especially the Friesian , Jersey breeds , and their crossbreeds to high-yielding of the imported exotic breed. Theileriosis in cattle 2. Vector & Transmission The disease causing intravascular hemolysis is transmitted by the bites of infected ixodid ticks, particularly the genus Hyalomma . The louse is localized in the tick's salivary glands and is injected into the host's bloodstream during the tick's feeding. 3. Pathogenesis: The cellular invasion The life cycle of Theileria in the cow host is remarkable and is comprised of two separate phases two-fold: Lymphoproliferative Phase: On entering, Sporozoites adhere to and invade the host Lymphocytes (White Blood Cells). They turn into the form of Schizonts, which tri...