Maternal Separation Affects Mothers’ Affective and Reproductive Behaviors as Well as Second Offspring’s Emotionality

Abstract

Daily separation of rat pups from their mothers while the preweaning period has an impact on behavior and stress response of pups. We hypothesized that maternal separation may create a depression-like state in mother rats from which we separate the rat pups and decrease their reproductive function and fertility. Also, we aimed to evaluate the transmission degree of depression and anxiety across generations. Females aged 3 months were divided in two groups of 10 rats each. After a first mating and a first parturition, we conducted maternal separation 3 h during 22 days for the experienced group while the control group mothers kept their pups. At 4 months of age, females underwent behavioral tests and a second mating. Second generation’s pups were also subjected to behavioral tests. Behavioral tests showed that mothers which experienced separation were more depressive and anxious than control ones, also they had a lower litter size. Rats pups of the second generation whose mothers experienced maternal separation also revealed behavior changes akin to depression and anxiety. Thus, maternal separation causes depressive and anxious-likestates on mother rats which experienced separation and has an impact on their litter size. Also, consequences of maternal separation seem to last throughout generations.