Dietary proteins on reproductive performance in three consecutive generations of rats

The cumulative effects of the long-term consumption of the Regional Basic Diet (RBD) of Northeast Brazil on gestational and lactational performances were assessed in three consecutive generations of Sprague Dawley rats (n = 1,334). The animals were distributed into three groups: RBD (8% predominantly vegetable-based proteins), Control (8% casein) and Standard (22% casein). Primiparous fertilized rats aged 120 days old and their offsprings made up generation 1. Consecutive generations were obtained by mating products from previous generations. Statistical differences between groups and generations were analysed by the method of Kruskal-Wallis. In comparison with their respective controls, data for RBD-fed groups were as follows: decreased conception rates, gradual declines in gestational body weight gains and reduction in the mean number of youngs per litter; the weight loss of lactating rats aggravated in consecutive generations; suckling rats had lower values for birthweight and weight gain, higher values for death rates (including soon after weaning) and severe immaturity at weaning (21 days). This dietary experimental model proved to be valid in terms of providing information for further studies about the relationship between quality and quantity of dietary proteins in order to allow decisions on supplementary feeding programmes for people now most in need.