Theileria annulata infection was detected in 46 Fresian Cows. Treatment measures were adopted. Serum samples were analysed before and 30 days after treatment for serum aspartate aminotrans ferase (S-G.O.T), serum alanine aminotransferase (S-G.P.J), total proteins and total bilirubin. Pretreatment levels of studied indices revealed liver function impairment that have ben restored at the 30th day following treatment.
Histopathological examination to parenchymatous organs of dead animals showed hepatic toxic jaundice, inflammatory oedema with compensatory emphysema of lungs, degenerative nephrosis with focal areas of inflammatory oedema in the interstitial tissues of the kidneys. Congestion of lymph nodes was evident.