Olfactory imprinting and age variables in the guinea-pig, Cavia porcellus

Abstract

In five experiments, guinea-pigs were reared with mothers and litter-mates which had natural (N), ethyl benzoate (Eb) or acetophenone (Ac) odours. When experimental odours were presented for 15 or 22 days, the guinea-pigs showed a preference for the rearing odour at 16 or 23 days of age when presented with a 5-hr choice of N, Eb or Ac stimulus animals. When exposed to Eb mother and littermates for only 6 days, they showed a decreased responsiveness to Eb animals at 16 and 23 days but days 1 to 6 were found to be more sensitive to olfactory exposure than either the 2nd or 3rd week exposure periods when tested at 16 or 23 days of age. A 3-day exposure period was found to be less effective than a 6-day period but the period 1 to 3 days of age was found to be more sensitive to olfactory imprinting than later 3-day exposure periods. As exposure duration to an experimental odour decreased, preference for N stimulus animals in tests increased. Regardless of age or duration of exposure to an experimental odour prior to 23 days of age, all groups generally showed a preference for the natural odour when tested at 60 days of age.