A maternal high-fat/high-caloric diet delays reflex ontogeny during lactation but enhances locomotor performance during late adolescence in rats.

Objective: The main goal of the present study was to investigate the effects of two maternal high-fat diets with different energy densities on the somatic growth, reflex ontogeny, and locomotor activity of offspring. Methods: Twenty-nine female Wistar rats (220-250 g) were mated and grouped into three different dietary conditions: control (n = 11, AIN-93G diet, 3.6 kcal/g), high-fat/high-caloric (HH, n = 9, 51% of the calories from fat, 4.62 kcal/g), and high-fat/isocaloric (HI, n = 9, 51% of the calories from fat, 3.64 kcal/g). The fat source was mainly lard. The dietary groups were maintained during gestation and lactation. From postnatal day 1 (PND1) until weaning, the somatic growth, maturation of physical features, and reflex ontogeny of the male pups were evaluated. The locomotor activity was evaluated in an open field at PND8, PND14, PND17, PND21, PND30, PND45, and PND60. Results: HH dams had a lower food intake but no difference in caloric intake or body weight gain. The HH pups had higher body weights, greater tail and body lengths, and an increased axis of the head at weaning. The prediction of ear unfolding, delayed palmar grasp, and cliff avoidance maturation were also observed in the HH offspring. At PND60, the HH pups showed an increased average speed as well as an average potency and kinetic energy in the open field. Conclusion: A high-fat/high-caloric maternal diet increases somatic growth, predicts the maturation of physical features, and delays reflex ontogeny during lactation, and it enhances motor performance during late adolescence. A maternal HI diet does not elicit the same influences on offspring development compared with the HH diet.