M. Champoux et Sj. Suomi, BEHAVIORAL AND ADRENOCORTICAL RESPONSES OF RHESUS MACAQUE MOTHERS TO INFANT SEPARATION IN AN UNFAMILIAR ENVIRONMENT, Primates, 35(2), 1994, pp. 191-202
The behavioral and adrenocortical responses of rhesus macaque mothers
to a series of four consecutive 4-day separations from their 5-month o
ld infants in an unfamiliar environment were examined. A biphasic beha
vioral response to separation was observed, with passive behavior, loc
omotion, and vocalization highest on Day 1 of separation, and self-dir
ected behaviors and environmental exploration peaking during Days 2 -
4. Stereotyped locomotion increased, and passive behavior decreased, a
cross successive weeks of separation. The rhesus mothers exhibited sub
stantial cortisol elevations one and two hours postseparation, with co
rtisol decreasing on the fourth day of separation. The cortisol respon
se was strongest during the first week of separation, but robust eleva
tions occurred in response to repeated separations. No signs of behavi
oral depression were observed. The results indicate that infant separa
tion combined with removal to a novel environment can be a potent stre
ssor for rhesus macaque mothers.