Early-life environmental events, like a disruption of the mother-pup relationship, may induce profound long-lasting changes upon several behavioral and neuroendocrine systems. A capacity that is critical for the pups in this period is identification of their mother, because she holds the vital elements for the pups’ survival. Rat pups recognize their mothers through olfactory cues. This early odor learning in rats is associated with increases in noradrenaline (NA) levels and cAMP response element-binding protein (CREB) phosphorylation in the olfactory bulb (OB). The present study aimed to analyze the effects of experimental handling of rat pups on the maternal odor preference test and the NA/CREB pathway participation. Wistar pup rats were daily handled for 1 min during the first 7 days (repeated handled group) or just once on day 7 after delivery (acute handling group). The acute handling group was divided in acute handled plus mother group, in which the pup was handled and returned to the mother for 15 min before humane killing, and the acute handled no mother group, in which the pup was handled and then was kept warmed for 15 min before humane killing. A nonhandled group, in which the pups were left undisturbed until day 7, was used as control. Parameters evaluated were: odor preference test, CREB, pCREB, NA and MHPG (noradrenaline metabolite) levels in the OB. Data were expressed as mean±SEM and the differences between groups (p≤0.05) were determined by Student’s t-test or ANOVA followed by Newman-Keuls test as required. Neonatal repeated handled pups showed increased latency to reach the nest bedding (268.2±10.6 s, n=12) compared with nonhandled pups (223.3±12.7 s, n=15). The frequency (F) and duration (D) of locomotion in the nest bedding area of repeated handled pups were decreased (F=3.8±1.2, D=10.3±2.5 s, n=12) compared with nonhandled animals (F=6.5±0.9, D=21.0±3 s, n=15). Acute handled plus mother (1941±201.9 optic density, n=5) and acute handled no mother groups (1756±95.8 optic density, n=5) showed increased pCREB levels compared with nonhandled group (1207±127.3 optic density, n=5). CREB levels did not change in the OB. Repeated or acute neonatal handling did not alter NA content, but MHPG increased in the repeated handled (1.3±0.1 pg/mg protein, n=7), acute handled no mother (1.2±0.01 pg/mg protein, n=7) and acute handled plus mother (1.3±0.1 pg/mg protein, n=7) groups compared with nonhandled (0.9±0.06 pg/mg protein, n=7). We may conclude that neonatal handling decreases maternal odor preference in rat pups. The increased activity of NA/CREB pathway in the OB seems to be involved in this change.