Maternal Separation Does Not Produce a Significant Behavioral Change in Mice.

Early life adversities together with genetic predispositions have been associated with elevated risks of neuropsychiatric disorders during later life. In order to investigate the underlying mechanisms, many chronic, early-life stress paradigms in multiple animal models have been developed. Previously, studies reported that maternal separation (MS) in the early postnatal stages triggers depression-and/or anxiety-like behaviors in rats. However, similar studies using mice have reported inconsistent behavioral outcomes. In this study, we sought to assess behavioral outcomes from two different early-life stress paradigms; a conventional 3-hour MS and a maternal separation with early weaning (MSEW) paradigm using C57BL/6J male mice with independent cohorts. Our data demonstrated that both MS and MSEW paradigms did not produce reported behavioral anomalies. Therefore, MS paradigms in mice require further validation and modification.