Major Depressive Disorder (MDD) is characterized by a constellation of symptoms, summarized into three major categories: passive coping strategies, anhedonia, and social impairment.The use of animal models can help to explore these symptoms and investigate their underlying mechanisms, such as oxytocinergic and opioids alterations within the mesocorticolimbic circuit.Exposure to Early Life Adversities (ELA), including Attachment Bond Disruption and Adverse Childhood Experiences, such as Neglect, represents one of the most important risk factors for development of MMD.To model attachment disruption and Neglect in animal models, we used two different paradigms of ELA (Repeated Cross Fostering; RCF - Neglect; Scarcity Model).The RCF is a protocol designed to interfere with pup-mother interaction, predisposing the offspring to separation anxiety, without inducing neglect by caregivers. RCF has been reported to increase depressive-like behavior in adult C57BL/6J male mice.The Scarcity Model is known to induce an abusive behavior by the dam without altering the attachment behavior, and to increase depressive-like behavior in adulthood. We chose to apply this paradigm in a narrower and earlier time frame than the one described in the literature: from PND1 to PND4, the same as RCF.Our preliminary data suggest that while RCF pups show separation anxiety, Scarcity pups experiencing abusive maternal behavior do not show this phenotype. In adulthood, while RCF animals exhibit increased passive coping and anhedonia, Scarcity animals show social impairment and increased anxiety. Finally, RCF and Scarcity mice are characterized by different oxytocinergic and opioids alterations within the mesocorticolimbic circuit.