Female rats exposed to early life scarcity-adversity are resilient to later life changes in maternal behavior

Abstract

In both humans and rodents, maternal care is disturbed by exposure to environmental adversity, including low resource conditions (i.e., poverty, scarcity). Maternal adversity is associated with compromised quality of mother-infant attachment and increased adverse caregiving patterns such as abuse, maltreatment and/or neglect, which disrupt behavioral development in the female offspring. Importantly, maternal behavior is thought to be an intergenerational behavior, meaning that the quality of maternal care a female experiences during early life is thought to influence the quality of care she will display towards her own offspring when she becomes a mother. Here, we tested this idea by employing a rodent model of postpartum environmental adversity based on creating an impoverished nesting environment during postpartum days (PD) 2–9, which disrupts mother-infant interactions and is thought to upregulate hypothalamic-pituitary-adrenal (HPA)-axis function in the pups. We examined the impact of this form of early life adversity on pup stress hormone (i.e., corticosterone- CORT) levels by collecting trunk blood and later life maternal behavior by conducting maternal behavior observations and maternal motivation tests (e.g., T-Maze, pup retrieval, pup-associated conditioned place preference) in the first filial (F1) generation. We report no impact of early life scarcity-adversity/adverse caregiving on pup CORT levels or later life naturalistic or motivated maternal behaviors. In sum, we show that female rat pups who experienced adverse caregiving during early life showed resilience towards developing negative caregiving patterns, as they did not perpetuate the same aberrant maternal behavior that they received from their mothers.