1. Chlorpyrifos : cause of ↗ the occurrence of obesity, associated with metabolic disorders and disturbances of digestive function in male offsprings ? 2. Prebiotic: limitation of observed disorders induced by the pesticide ? 4 MONTHS (16 WEEKS) 3 WEEKS 3 WEEKS 9 WEEKS EXPERIMENTAL CONDITIONS MOTHERS (N=16) 10g/L in drinking water  Family of organophosphorus  Insecticide action CHLORPYRIFOS (CPF) Oral gavage : 5 days / week (1mg/kg bw/d) Kruskal Wallis with Dunn's post test or ANOVA with Bonferroni's post test ; GraphPad Prism version 5.00-*p<0,05; ** p<0,01; *** p<0,001 Animal team, PlatAnN animal facility platform, and Aurélie Corona, laboratory technician PériTox UMR-I-01, Amiens, France INULIN (i)  Food fiber (b 2-1 fructane)  Prebiotic effect Perinatal period is characterized by a succession of developmental phases with high sensitivity to environmental factors. Among the risk factors, pesticide exposure is now recognized to reprogram children's metabolism and promote the occurrence of obesity or type 2 diabetes. This work was dedicated to the peri-gestational exposure of dams to a low dose of pesticide (chlorpyrifos, CPF) and the exploration of the prebiotic supplementation benefits