Studies of sheep experimentally poisoned with Hypericum perforatum.

Sheep given different dosages and frequencies of Hypericum perforatum had decreased hemoglobin, red blood cell count, packed cell volumes, total protein, glucose, cholesterol, triglycerides, and serum alkaline phosphotase activities. Blood urea nitrogen, sodium, potassium, bilrubin (total and direct), and the activities of aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase and gamma glutamyltransferase increased. Hemato-biochemical assays were useful diagnostic aids to determine the severity of this plant's toxic effects.