CHANGES IN RESPONSIVENESS TO YOUNG IN ADULT MOUSE .V. PRIMING

Twenty experimental animals (naïve female mice) were presented for 5 min with a 1 to 2-day-old pup hidden in a small metallic box, thus providing only olfactory and auditory cues. Their later maternal behaviour with a weak stimulus (dead 1-day-old pup) was then compared with that from twenty totally naïve control females. Results showed that maternal responses towards the dead pup were greatly increased after the exposure to the hidden pup. Retrieving, licking and nest-building were seen in significantly more experimental than control females. Also, when occurring, these behaviour patterns tended to be given earlier in the experimental condition. Licking and nest-building were more often repeated and lasted for longer periods in the experimental group. The possibility of this increase being different from a conditioning process is briefly discussed. © 1969.