Abstract # 2125 Poster # 68:

Scheduled for Thursday, June 21, 2007 05:00 PM-07:00 PM: Session 7 (South Main Hall) Poster Presentation

Mother-only Rearing in Nuclear Family Caging Produces Species-typical Behavioral Development in Rhesus Monkeys (Macaca mulatta)

M. L. Miller1, L. Darcey1, A. M. Ruggiero1, M. L. Schwandt2, C. S. Barr2, S. J. Suomi1 and M. F. S. X. Novak1
1NICHD, NIH, Laboratory of Comparative Ethology, NIH Animal Center, Poolesville, Maryland 20837, USA, 2Laboratory of Clinical and Translational Studies, NIAAA
     Historically, mother-only rearing was unsuccessful at producing species-typical development in infant macaque monkeys (Macaca spp.). A modification of caging for this condition was recently designed allowing mother-only reared infants to cross freely back and forth through a small tunnel to an adjacent cage without the mother being able to follow, called nonsocial-mother rearing (NMR). The hypothesis was the increased autonomy afforded to the infant would inhibit the high levels of mother-infant clinging typically observed and allow the development of more species-typical behavior in the infant. This study compares the behavioral repertoire of rhesus macaque infants in this rearing condition to the standard social group mother rearing (MR), peer-peer rearing (PR), and surrogate-peer rearing (SPR). Using focal animal sampling, social behavior for all four conditions was collected for five minutes twice weekly from week 9 until week 24. Repeated measures ANOVA detected some pairwise individual rearing group differences. However no differences existed between MR and NMR conditions for social contact, play behavior, ventral clinging, stereotypy, self directed behaviors or self mouthing [all p>0.05]. Furthermore, ventral clinging in the NMR group diminished with age in a species typical fashion [Greenhouse-Geisser F(10.6,169.3)=23.0, p=0.012]. NMR infants displayed more environmental exploration than all three other rearing conditions [F(3,35)=14.8, p<0.001]. Using the modified caging system, this kind of nonsocial-mother rearing may be a viable alternative for studies interested in mother-infant behavior. Supported by intramural research program of NICHD-NIH.