This study was included the detection of the infection with Sarcocystis gigantean in sheep, the mature cystic stages was appeared oval or cylindrical shaped with a diameter of 7.8 2.8 mm and 1.5 μm thick striped cyst wall. The total rate of infection with the macroscopic type in sheep oesophagus reached 94.8%.
Isolation and precipitation of crude protein extracted from macrosarcocysts of S. gigantea was performed using saturated ammonium sulphate solution. Fractions of this protein (a and b) were isolated by employing Gel Filtration Technique on Sephadex G-50. The molecular weight of these proteins fractions were determined as about 63095 and 27410 dalton respectively using (SDS-PAGE) electrophoresis technique.
The toxic effect of b protein fraction was studied in rats peritoneal injection at concentration 0.1, 0.3, and 0.5 mg /kg body weight. These animls experienced acute doxicological nervous signs including tremors, complete and partial paralysis. The highest dose (0.5 mg/kg) of b fraction was the most toxic among the injected concentrations. Blood picture in injected rats revealed a significant reduction in hemoglobin and packed cell volume and increase in total leuckocyte count. Significant increase in serum aspartate aminotransferase and alanine aminotransferase enzymes were observed. There was also a significant inhibition in the brain cholinesterase activity in the treated rats.