Starvation-Induced Ovine Toxemia: A Re-Evaluation

Abstract

A syndrome of hypertension, proteinuria, thrombocytopenia and plasma prostaglandin alterations similar to human preeclampsia has been reported to be consistently induced by 72 hours of starvation in near-term twin-gestation ewes. To confirm this model, six mixed-Western and four Dorset twin gravid ewes of known gestation were prepared with fetal and maternal intravascular catheters. Following recovery (132 days), food was removed from the ewes' cages for 72 to 96 hours. In response to starvation, there was no significant increase in mean arterial pressure in either breed of sheep. Furthermore, there was no difference in the maternal arterial blood pressure response to intravenous graded infusions of angiotensin II (AII) (5, 10, and 25 ng/kg/min) prior to and following starvation of Dorset ewes. Maternal starvation did not result in fetal acidosis or hypoxia. The results suggest that hypertension and increased sensitivity to angiotensin II are not consistent findings in starved twin-bearing gravid ewes.