Response to glucose infusion in pregnant and nonpregnant ewes: changes in plasma glucose and insulin concentrations

The aim of this study was to evaluate the effect of a glucose load in pregnant and nonpregnant Sardinia ewes. After ultrasound diagnostic exam, 15 ewes were divided into 3 groups of 5 subjects each: group A (nonpregnant ewes), group B (pregnant ewes with one fetus), and group C (pregnant ewes with twin fetuses). On all blood samples collected through jugular venipuncture, plasma glucose concentration was assessed by means of a UV spectrophotometer and plasma insulin concentration was assessed by means of a radioimmu- noassay kit. All measurements were taken 15 min before glucose infusion, 5, 10, 15, 30, 45, 60, 90, 120, and 240 min after glucose infusion. Two-way repeated measures analysis of variance followed by the Tukey’s test showed statistical differences (P < 0.05) on glucose and insulin concentrations. These results showed the influence of the glucose load on metabolism of ruminants and indentified the glucose as an important direct controller of metabolic interactions in normal subjects and of metabolic responses in pregnant ewes.