A nutty idea: Exploring a novel method using a hazelnut cocoa spread to temporarily increase maternal care behavior within a rat litter.

Maternal care plays a crucial role for infant development. In humans, skin-to-skin care is often used for preterm infants to reduce acute stress and improve long-term developmental outcome. Here we propose a new translational approach to study the effects of acute increases in maternal care on offspring development in rodents. First, pilot studies determined that dams spent more time licking pups covered in hazelnut cocoa spread (Nutella® )) than any other studied substance. For the main experiment, Sprague-Dawley rats were bred in-house, and Nutella® was applied four times a day to treatment pups (2 males/females per litter) of seven litters from PN2 to 5. Control pups (2 males/females per litter) were handled similarly without applying any substance. Maternal licking and grooming behavior was observed for 30 min following each Nutella® application. Nutella® -covered pups received significantly more licking and grooming compared to control pups within each litter. There was no difference in body weight or basal serum corticosterone levels between Nutella® -covered and control pups on PN5, suggesting that the Nutella® application and subsequent increased maternal licking was not stressful for the pups. Future studies will investigate whether this increase in maternal care can protect pups from stress- or pain-induced rises in corticosterone.