Glucose tolerance, insulin sensitivity and pups body composition. Glucose tolerance, insulin sensitivity and pups body composition according to weaning age d16, d21 or d26 in male adult F1 rats on d80 to 90. (A). Enteral glucose tolerance test: after six hours fasting, 0.1 g/ml glucose was given intragastic through a feeding tube to provide 1 g glucose for each 100 g body weight. (B) Insulin tolerance test: Rats were injected intraperitoneally with insulin (0.75 U/kg) and blood glucose was measured by glucometer. (C) For assessment of body composition, d10 rats of F2 generation, whose parents weaned on d16 (dark bars) or d26 (white bars), were tested by live-mice TD-NMR Analyzer. The onboard electronics calculated fat and lean (mostly muscle) mass per 100 g body weight (% fat is multiplied by 10 for clarity). Statistically significant differences between d16 and d26 rats are indicated by (*) for P <0.05 with a two-way t-test. Mean ± SEM, n = 6 per group.