Abstract # 167:

Scheduled for Friday, August 19, 2005 07:00 PM-09:00 PM: (Cambridge/Oxford Room) Poster Presentation

Behavioral Development in Intensively-Handled and non-Intensively Handled Nursery-Reared Rhesus Macaque (Macaca mulatta) Neonates

N. Wang, S. J. Suomi and C. Lindell
NICHD, 2600 Hawkshead Ct., Silver Spring, MD 20904, USA
     Intensive human handling is thought to promote normal primate biobehavioral development in nursery settings, although the specific effects of handling are unclear. To better evaluate handling effects, we observed the individual and social behaviors of 39 nursery-reared rhesus macaque infants. All infants were observed up to 6 months of age; 19 received additional handling while 20 did not. Individual and social behavioral data were collected in 5-minute focal sessions twice a week, and data were analyzed using repeated measures analyses of variance and Tukey-Kramer pair-wise comparisons. We hypothesized that handled infants would exhibit increased exploratory, social, and play behavior and decreased abnormal behaviors such as self-clasp. Handled infants demonstrated significantly less individual environmental manipulation (P < 0.05), locomotion (P < 0.01), motion (P < 0.001), and play (P < 0.001) and more passive behavior (P < 0.001) and sleep (P < 0.01). No differences in abnormal behaviors were found. In social settings, handled infants showed less locomotion (P < 0.05) and passive behaviors (P < 0.05) and more social contact (P < 0.01) as compared to non-handled infants. Thus, we found that handled infants do not show more individual exploratory behavior, but do show increased social behavior. Although it is unclear why handling is correlated with more individual passive behaviors, it seems that the effects of handling are most pronounced in social settings. Increased social activity among handled infants may be due to social contingencies learned through interaction with humans and other infants during handling.