Alloxan-induced diabetes mellitus in pregnant sheep and chronic fetal catheterization:

25 female sheep of the Texel breed were made hyperglycaemic by administration of alloxan monohydrate (ALX) in early pregnancy and 15 ewes served as controls. Average venous glucose levels (mean ± standard deviation) increased from 3·5 ± 0·2 to 14·0 ± 1·8 mmol/l. All hyperglycaemic sheep were treated with long-acting insulin in doses adjusted individually (0·2-1·0 U/kg per day) to keep glucose levels above 8 mmol/l. After a temporary significant increase, maternal venous concentrations of urea and creatinine returned to normal levels.One sheep died on day 6 after administration of ALX. Another hyperglycaemic sheep died at induction of anaesthesia. Eight hyperglycaemic ewes aborted between days 90 and 128 of gestation. Between days 103 and 135 of gestation the remaining hyperglycaemic (n = 15) and control (n = 15) ewes were operated upon and the fetuses were provided with EEG, nuchal EMG and ECG electrodes and catheters in the trachea, amniotic fluid, jugular vein and carotid artery.Use of the chronic sheep...