Maternal separation and post-weaning feeding behavior in rodents: A critical review and meta-analysis

Child neglect is a worldwide phenomenon that is associated with an increased risk of suffering from eating disorders. We aimed to examine the impact of child neglect on eating behaviors using two animal models of developmental disruption, maternal separation and maternal deprivation (MS and MD). The search resulted in 38 relevant studies, and datasets were divided into two meta-analytical analyses - for regular and palatable food intake (RFI and PFI). Procedure, sex and developmental stage were investigated as potential moderators in the RFI analysis and procedure, sex and main macronutrient in palatable food were investigated as potential moderators in the PFI analysis. MS increased RFI in males regardless of developmental stage, and reduced RFI in adult females. MS also increased PFI in both sexes but the main component in the palatable diet moderated the effect of MS on PFI only in males, whose consumption of palatable foods increased when the food was rich in carbohydrates and decreased when the food was rich in carbohydrates and lipids/fats. Thus, MS may influence feeding behaviors that resemble aspects of anorexia nervosa and binge-eating like behavior in adult females (depending on the diet) and alter males' hunger and satiety signalling. Additionally, MD reduced RFI and PFI in both sexes, indicating that MD is a useful model for altered behavioral eating pattens that relate to depression. Further research is needed given the existence of publication biases, and the high, unresolved heterogeneity between effect sizes.