Abstract # 2049 Poster # 195:

Scheduled for Friday, August 18, 2006 07:00 PM-09:00 PM: Session 17 (Regency West 1/3 ) Poster Presentation

Longevity of effects of early rearing experience on behavioral response to social separation in adult rhesus macaques (Macaca mulatta).

C. A. Corcoran1, J. L. Christenson1, S. J. Suomi2 and A. J. Bennett1
1Wake Forest University Health Sciences, Winston-Salem, NC, USA, 2The laboratory of Comparative Ethology, The National Institute on Child Health of Human Development, NIH, Poolesville, MD 20837, USA
     Previous research has shown that early nursery-rearing increases susceptibility to stress in some individuals. We compared the effects of social separation on behavior in 10 rhesus monkeys either nursery (n=5; NR) or mother-reared (n=5; MR) in the first 6-months of life. Nursery- and mother-reared monkeys were housed socially following weaning at 7-months of age until they reached five years and were rehoused for a separate study that required single housing. Focal animal observations of locomotor behavior were made via videotapes recorded prior to, the day of, and following transfer from social to single housing. Locomotion decreased following social separation, F(1,8)=35.087, p<0.01. NR monkeys locomoted less compared to their MR counterparts, F(1,8)=18.9, p<0.01. Nursery-reared monkeys also showed a greater initial reduction of locomotion following the social separation (t=2.55, p<0.05) and their locomotion continued to be blunted throughout all observations (t=3.308, p<0.05). In contrast to their nursery-reared counterparts, mother-reared monkeys showed faster habituation following the relocation, as reflected by a return to baseline locomotor levels by the second observation. Further evidence of disruption in the behavior of the NR group was shown through a trend towards a greater number of sessions showing the presence of stereotypic behaviors following separation, ?2(3, N = 10) = 7.00, p < 0.10. Taken together, our data demonstrate long-lasting effects of differential early rearing experiences on behavioral response to social separation and environmental change and suggest that these effects are not ameliorated by intervening years of social housing. Supported by NIH grants AA13995, AA011997, AA014106.