Post-natal maternal stress decreases locomotor play behaviors in Octodon degus pups

Play behaviors are generally considered to be beneficial and necessary for young, developing animals. Expression of play, however, is sensitive to several post-natal factors including maternal care. In this study, we observed whether maternal stress and maternal care behaviors were related with adolescent play behavior in the degu (Octodon degus), a diurnal rodent species native to central Chile. By observing pairs of mothers that were either unstressed (habituated to captivity) or stressed (only recently introduced into captivity), the frequencies of both social and locomotor play behaviors in the offspring, along with general behaviors and time of rest, were scored from 2 to 20 days after parturition. All scored play behaviors increased in frequency over time, indicating that degu pups become more active and playful as they mature. Additionally, we also found that pups from unstressed mothers expressed higher frequencies of locomotor play behavior (Running and Frisky Hops) and some social affiliation behaviors (Nose-to-Nose Contact) compared to pups from stressed mothers. Furthermore, these behaviors were significantly and positively related with the amount of maternal care received. Our results suggest that development of certain play behaviors are affected by maternal stress, likely via alterations in maternal care.