Some changes in the composition of maternal and fetal plasma from chronically catheterised sheep during short periods of reduced feed intake in late pregnancy.

Changes in the composition of maternal and fetal plasma from nine sheep were followed during periods of reduced feed intake lasting four to seven days. Feed rations were reduced between 120 and 128 days of gestation and this produced hypoglycaemia in mother and fetus. In each sheep there was a significant negative correlation between the glucose and corticosteroid concentrations in both maternal and fetal plasma, and there were positive correlations between the maternal and fetal plasma concentrations of glucose, and between the glucose and fructose concentrations of fetal plasma. Maternal and fetal packed cell volumes and the plasma concentrations of lactate and thyroxine remained relatively constant.